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Muscletang needs new floor pans - advice?


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Good points. Then it doesn't make sense. Could it be that they cut it to check for damage or rust? But if so, why cut it so much.

I thought of an accident because that door doesn't close as easy, but that could also be some misalignment of the hinges or lock.

 

How are your door gaps?

 

Here is a picture.

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1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

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Hard to tell with the bump strip on the back of the door. Same on my '71. Wouldn't dare remove them - they'll take your paint with 'em.

 

-Kurt

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How to buy a '71-73 Mustang:

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Make sure you weld the pan in. DONT use adhesive, the floor is a major structural part of the car. If you don't mind seeing the seam, make it easy on yourself and overlap the seams. I butt welded mine and you cant even tell its there, but its time consuming and pretty challenging if you have never welded before. Buy a good spot weld cutter and some bits for it. Also get a cheap flanger/punch tool from harbor freight so you don't have to drill 100 holes by hand! http://www.harborfreight.com/air-punch-flange-tool-1110.html

Good tip about the butt weld bits. Didn't know them. I found this Blair set in Amazon: http://www.amazon.com/gp/product/B002XML5HK/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A1UMBRA5ZTBCX8 Are those good?

I don't have a big enough air compressor to run air tools. Forgive my lack of knowledge, what are the holes you talk about for? I am planing on going the lap joint weld route.

 

Blair makes a good spot weld cutter but make sure you don't use the one with the center drill bit. you want the one with a pin in the center. Make sure you center punch the spot welds really good before drilling so the bit doesn't walk all over the place and break.

When you weld your pan in at the lap joint I would just punch holes around the edge every 1 1/2 inches and do rosette welds. You can weld the entire perimeter, but I don't think its necessary. A bunch of nice tight spot welds will do the trick. You don't need much of an air compressor to use that tool I linked you to. It sure beats drilling a bunch of holes. You can use some self tapping screws to pull the panels tight together for the welds. Then after welding take out the screws and weld up the holes. After your done you can use some 3m seam sealer in a caulking gun to seal the lap joints both top and bottom of the car. Here is an example of the welds. NOT a mustang but will give you an idea, a 59 Studebacker I put floor pans in. Last pic is just one I found online.

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Kevin
1971 Mach 1

408C Stroker - C4 w/3,000 stall - 8.8" Rear w/3.73's - Disc brakes all way around.

 

 

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Blair makes a good spot weld cutter but make sure you don't use the one with the center drill bit. you want the one with a pin in the center. Make sure you center punch the spot welds really good before drilling so the bit doesn't walk all over the place and break.

When you weld your pan in at the lap joint I would just punch holes around the edge every 1 1/2 inches and do rosette welds. You can weld the entire perimeter, but I don't think its necessary. A bunch of nice tight spot welds will do the trick. You don't need much of an air compressor to use that tool I linked you to. It sure beats drilling a bunch of holes. You can use some self tapping screws to pull the panels tight together for the welds. Then after welding take out the screws and weld up the holes. After your done you can use some 3m seam sealer in a caulking gun to seal the lap joints both top and bottom of the car. Here is an example of the welds. NOT a mustang but will give you an idea, a 59 Studebacker I put floor pans in. Last pic is just one I found online.

 

 

 

 

 

Thanks. These are very helpful tips. This is a very doable project. I can't wait to get going. I ordered the Blair cutter you recommended, #11082 w/o pilot bit. The panels are backordered at CJ Pony, but I still have ways to go before I start welding them together. I first have to remove some of the fiberglass to locate the factory spot welds, cut them, remove the seat risers, cut the old panels out, cut the new panels in, drill and then lap weld. After that I guess seal, paint, and enjoy!

BTW, what 3M seam sealer do you recommend? I searched and there are many options.

 


This forum is amazing. Your help is greatly appreciated and thanks for giving me the confidence to tackle this job and the many others I have asked questions about.

20160929_171923_edit2_small.jpg

 

1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

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The saga continues tonight. I peeled away more and more of the fiberglass to find the floors in very bad shape. I am kind of afraid of peeling more to find bad news. I am sure a lot of you have gone through this. I don't yet know how far up into the firewall and into the transmission tunnel the replacement floor pans go. I also found out that the driver's seat riser is a goner and found some rust starting though under the rear seat panel (name??).

Questions:

-Where is a good source for the sear riser pan? I found one at $75. Also, is the pan under the rear seat fabricated? the rust under the rear seat appears minor, but still have to investigate more.

-The passenger seat riser does not look like the driver's side. The passenger was probably replaced when the car was restored 12 years ago. The riser has some areas of spot welds and some areas where they welded the edges (see picture). I assume that I take out the edge welds with the grinder.

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20160929_171923_edit2_small.jpg

 

1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

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Honestly, I'm only seeing surface rust in the rear seat area - perhaps it's the photo. The rot spots around the pedal area should be covered by the new pans. The riser will come out anyway for the installation, so you shouldn't have a problem.

 

That appears to be an original Ford replacement seat riser on the passenger's side, not the current repop (which only comes in the taller Coupe size, and is a nasty-looking piece of workmanship). You're lucky that this side is OK. I'd recommend sourcing a good original for the driver's side. It'll save you some installation headaches.

 

-Kurt

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How to buy a '71-73 Mustang:

Rule #1: Assume all classic car sellers are guilty until proven innocent.

Rule #2: No classic car dealer is ever innocent; thus, they are all guilty.

Rule #3: Buy from trustworthy people: Fellow forum members. Visit 7173Mustang's For Sale forum.

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Your floor pans aren't crazy bad! The new pans will go up the trans tunnel 4-5 inches, so you will definitely cover your bad spots. The rear seat area doesn't look too bad. Wire wheel it and clean it up, then rust bullet the crap out of it. Should be fine. If your passenger seat pan is good try to save it. And CUDA is right about the repops only being for coupe and convertible, but you can easily trim them down to fit properly. If you can find a good used seat riser that would be easiest, but they are usually rotted on the bottom edge. I put the repops in my mach1 and they needed trimmed down to fit and while I was at, I moved them back about 2 inches for a little more leg room.

As far as what seam sealer to use, I just go to the local autobody supply shop and tell them I need body seam sealer in a caulking gun tube. They usually give me a 3m brand ,but I cant remember what it is off hand....sorry. Its not cheap...almost $20 a tube! But its good sticky stuff!!

If you have any more questions let us know! And don't forget the progress pics!!!

Kevin
1971 Mach 1

408C Stroker - C4 w/3,000 stall - 8.8" Rear w/3.73's - Disc brakes all way around.

 

 

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If you can find a good used seat riser that would be easiest, but they are usually rotted on the bottom edge. I put the repops in my mach1 and they needed trimmed own to fit and while I was at, I moved them back about 2 inches for a little more leg room.

 

I have a pair of used pans with the risers on them - the driver's side is not great, but it may be better than what he has now.

 

I'll pull it out and take a photo for Tony this weekend. So long as I don't need it for the yellow car, I don't mind parting with it.

 

-Kurt

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How to buy a '71-73 Mustang:

Rule #1: Assume all classic car sellers are guilty until proven innocent.

Rule #2: No classic car dealer is ever innocent; thus, they are all guilty.

Rule #3: Buy from trustworthy people: Fellow forum members. Visit 7173Mustang's For Sale forum.

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I have a pair of used pans with the risers on them - the driver's side is not great, but it may be better than what he has now.

 

I'll pull it out and take a photo for Tony this weekend. So long as I don't need it for the yellow car, I don't mind parting with it.

 

-Kurt

 

Thank you Kurt, let me know.

 

1971 M-code Mach 1


 

The rear seat area has couple small areas where is rusted through. On the drivers side there is another fiberglass patch which i am afraid to remove. The picture is not the best.

That said, do i need to cut and weld some sheet metal to it, or is there another way to go.

 

1971 M-code Mach 1

20160929_171923_edit2_small.jpg

 

1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

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I have a pair of used pans with the risers on them - the driver's side is not great, but it may be better than what he has now.

 

I'll pull it out and take a photo for Tony this weekend. So long as I don't need it for the yellow car, I don't mind parting with it.

 

-Kurt

 

Thank you Kurt, let me know.

 

1971 M-code Mach 1


 

The rear seat area has couple small areas where is rusted through. On the drivers side there is another fiberglass patch which i am afraid to remove. The picture is not the best.

That said, do i need to cut and weld some sheet metal to it, or is there another way to go.

 

1971 M-code Mach 1

 

You will need to cut out any holes and weld in some patches.....couldn't tell from the pics sorry. If its where the lower seat cushion sits, I don't believe they make patch panels for that area??? I may be mistaken but im sure someone on here knows for sure!! If not get some 16 gauge steel and cut a few patches for that area. the smaller patches are a little easier to practice your butt welding skills if you would like or you can just overlap it....up to you.

Kevin
1971 Mach 1

408C Stroker - C4 w/3,000 stall - 8.8" Rear w/3.73's - Disc brakes all way around.

 

 

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The rear seat area has couple small areas where is rusted through. On the drivers side there is another fiberglass patch which i am afraid to remove. The picture is not the best.

That said, do i need to cut and weld some sheet metal to it, or is there another way to go.

 

Rip up the fiberglass. Do it once, and do it right.

 

It's just steel replacement, and it's not even on the outside of the car. You're lucky!

 

-Kurt

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How to buy a '71-73 Mustang:

Rule #1: Assume all classic car sellers are guilty until proven innocent.

Rule #2: No classic car dealer is ever innocent; thus, they are all guilty.

Rule #3: Buy from trustworthy people: Fellow forum members. Visit 7173Mustang's For Sale forum.

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Thank you for the encouragement guys. Tonight after seeing the Badgers lose to Duke I released my frustration working on the car. I ended up removing most of the fiberglass in the area under the rear seat. Here are the pictures. There are areas with surface rust, some areas where pitting already started and some other areas where there are holes through.

Here is what I am thinking, but I need advice on how to properly proceed.

-The areas with surface rust are easy: clean/grind rust.

-The areas with surface pitting: this is a bit of an unknown. I guess I will start with cleaning/grinding the rust. Then check thickness. If too thin may have to replace area. However, how thin is "too" thin?

-The ares with through holes: replace local sheet metal plus clean and grind. I am thinking to cut holes around the area with a hole saw. Then I can use the same hole saw in new sheet metal and weld. Or cut sheet metal larger and lap join with adhesive. It may be trickier in the areas where folds exist. I will have to try replicating these folds as close as possible.

 

Two other questions about the second to last and last pictures.

-The second to last is the area where the fender meets the underseat panel. I started cleaning and started removing some black sealant. I assume this is the factory sealant so I stopped. The good news is that the area underneath is shiny sheet metal. Now, once I prime and seal that area how do I ensure that the union between the old sealant and new is proper?

-The last picture is the passenger's side where the underseat panel meets the floor panel and other sheetmetal. Hard to describe but hopefully the picture shows it. My question here, does this look factory? There is a gap between the panels in the lower right area of the picture that shows a larger than expected gap (circled area). You can actually see the garage floor through this gap.

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20160929_171923_edit2_small.jpg

 

1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

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Thank you for the encouragement guys. Tonight after seeing the Badgers lose to Duke I released my frustration working on the car. I ended up removing most of the fiberglass in the area under the rear seat. Here are the pictures. There are areas with surface rust, some areas where pitting already started and some other areas where there are holes through.

Here is what I am thinking, but I need advice on how to properly proceed.

-The areas with surface rust are easy: clean/grind rust.

-The areas with surface pitting: this is a bit of an unknown. I guess I will start with cleaning/grinding the rust. Then check thickness. If too thin may have to replace area. However, how thin is "too" thin?

-The ares with through holes: replace local sheet metal plus clean and grind. I am thinking to cut holes around the area with a hole saw. Then I can use the same hole saw in new sheet metal and weld. Or cut sheet metal larger and lap join with adhesive. It may be trickier in the areas where folds exist. I will have to try replicating these folds as close as possible.

 

Two other questions about the second to last and last pictures.

-The second to last is the area where the fender meets the underseat panel. I started cleaning and started removing some black sealant. I assume this is the factory sealant so I stopped. The good news is that the area underneath is shiny sheet metal. Now, once I prime and seal that area how do I ensure that the union between the old sealant and new is proper?

-The last picture is the passenger's side where the underseat panel meets the floor panel and other sheetmetal. Hard to describe but hopefully the picture shows it. My question here, does this look factory? There is a gap between the panels in the lower right area of the picture that shows a larger than expected gap (circled area). You can actually see the garage floor through this gap.

 

Looks like someone in the past used rust bullet type stuff or undercoating type stuff on the pans...hard to tell from the pics. That will hide a lot! Grind, wire wheel it off and clean that area up. I usually cut the small holes out with a body saw or cutoff wheel and make them square. A hole saw might distort your new patch. ??? Since you will be welding in the floor pans you might as well weld in all the patches. My personal preference is to weld anything I can. One way to tell if the metal is too thin....use a screw driver and try to poke through it. If you poke through it....too thin if not then your good. Use good common sense and judgment. Those small holes I would cut a nice square hole out and butt weld it in place for a seamless look, but if your not comfortable with that, then by all means do a lap joint weld. With the sealer new meeting old..... just make sure if you use the stuff from a caulking gun don't just make a nice bead and leave it there. You always want to run your finger down it to make sure it seals well and gets smoothed out nice. Just like caulking windows or a shower in your house. The last pic is really hard to see. but if its a seam in the panels coming open then you will want to clean it up and try to pull it together with a c-clamp or self tapping screw if possible, then weld it shut and grind it to look nice. good luck!!!

Kevin
1971 Mach 1

408C Stroker - C4 w/3,000 stall - 8.8" Rear w/3.73's - Disc brakes all way around.

 

 

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The last pic is really hard to see. but if its a seam in the panels coming open then you will want to clean it up and try to pull it together with a c-clamp or self tapping screw if possible, then weld it shut and grind it to look nice. good luck!!!

 

Thanks for your responses. Here is a close-up but still not easy to see. It does not seem like coming apart. It just looks like the two panels were welded a bit a part. Teh gap is fairly consistent. It looks original or nicely redone. I just don't know if this is normal. I can try to add sealant and then close the gap with a clamp. If it is original welding it shut may not be the proper way.

Actually, some water comes through this hole while driving because the inside plastic panel had some water splash marks. Speculating, that could explain the rust. If water came up through there during driving the area may have stayed wet causing rust over time. It is weird that the car appears in such a good shape everywhere except these floor pans.

20141204_001636_resized-cropped.jpg.cac49ed636e16a2b7bbe59b1bed7f68e.jpg

20160929_171923_edit2_small.jpg

 

1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

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The last pic is really hard to see. but if its a seam in the panels coming open then you will want to clean it up and try to pull it together with a c-clamp or self tapping screw if possible, then weld it shut and grind it to look nice. good luck!!!

 

Thanks for your responses. Here is a close-up but still not easy to see. It does not seem like coming apart. It just looks like the two panels were welded a bit a part. Teh gap is fairly consistent. It looks original or nicely redone. I just don't know if this is normal. I can try to add sealant and then close the gap with a clamp. If it is original welding it shut may not be the proper way.

Actually, some water comes through this hole while driving because the inside plastic panel had some water splash marks. Speculating, that could explain the rust. If water came up through there during driving the area may have stayed wet causing rust over time. It is weird that the car appears in such a good shape everywhere except these floor pans.

 

If you can see that seam under the car. Check it out and make sure the spot weld look good and did not come apart. If they look good and that's factory then clean it up and fill the seam with seam sealer. But you are right seems like a pretty wide gap.?? You can always clean it up and add some weld to it to ensure it wont open any more then seam seal it to keep the weather out. Hard to say without seeing this kinda stuff in person.

Kevin
1971 Mach 1

408C Stroker - C4 w/3,000 stall - 8.8" Rear w/3.73's - Disc brakes all way around.

 

 

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Actually, some water comes through this hole while driving because the inside plastic panel had some water splash marks. Speculating, that could explain the rust. If water came up through there during driving the area may have stayed wet causing rust over time. It is weird that the car appears in such a good shape everywhere except these floor pans.

 

Tony, I'll snap some photos of this joint on my '72 parts car and the '71.

 

-Kurt

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How to buy a '71-73 Mustang:

Rule #1: Assume all classic car sellers are guilty until proven innocent.

Rule #2: No classic car dealer is ever innocent; thus, they are all guilty.

Rule #3: Buy from trustworthy people: Fellow forum members. Visit 7173Mustang's For Sale forum.

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I was out of town early in the week so finally had some time to grind and clean a little more. Tons of bondo to clean. I am finding out that the rear driver's floor pan was replaced at some point. They used tons of bondo and a terrible welding job. The pan is welded on top of the seat riser.

Please look at the pictures and please advise on what's the best way to cut the welds around the floor pan. I guess some of them I can cut with the cutting wheel but it will be a challenge, specially in the area shown in the last picture where the panel is welded to the tunnel. Crazy!

Picture 1: driver's rear floor pan edge against seat riser

Picture 2: seat riser edge against tunnel

Picture 3: driver's rear floor pan edge against tunnel

 

Edit: I may have answered my last question. Looking at the replacement pans it looks like they go high up the tunnel so I may have to cut the tunnel just above the weld.

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20160929_171923_edit2_small.jpg

 

1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

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If your putting in full length pans on both sides, just cut out the old pans and seat risers. If they overlapped the seat riser it may be pretty difficult to get them apart. But it would be easier to try to separate them on your work bench. If you cant get them apart just bite the bullet and buy the new seat risers and cut them down to fit you. Its not too hard to do and you can cut them as much or as little as you like to get a custom fit for yourself. I left my replacement passenger side seat riser alone because my wife is pretty short and it helped her see over the dash and hood. I only modified the drivers seat riser. Hope this helps some.

Kevin
1971 Mach 1

408C Stroker - C4 w/3,000 stall - 8.8" Rear w/3.73's - Disc brakes all way around.

 

 

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If your putting in full length pans on both sides, just cut out the old pans and seat risers. If they overlapped the seat riser it may be pretty difficult to get them apart. But it would be easier to try to separate them on your work bench. If you cant get them apart just bite the bullet and buy the new seat risers and cut them down to fit you. Its not too hard to do and you can cut them as much or as little as you like to get a custom fit for yourself. I left my replacement passenger side seat riser alone because my wife is pretty short and it helped her see over the dash and hood. I only modified the drivers seat riser. Hope this helps some.

So if I understand correctly, the modification of the new riser will require to cut the vertical sheet metal and then reweld, correct? Anything else?

Is there a writeup thread for this? I looked but may have to try again.

Thanks.

 

1971 M-code Mach 1

20160929_171923_edit2_small.jpg

 

1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

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If your putting in full length pans on both sides, just cut out the old pans and seat risers. If they overlapped the seat riser it may be pretty difficult to get them apart. But it would be easier to try to separate them on your work bench. If you cant get them apart just bite the bullet and buy the new seat risers and cut them down to fit you. Its not too hard to do and you can cut them as much or as little as you like to get a custom fit for yourself. I left my replacement passenger side seat riser alone because my wife is pretty short and it helped her see over the dash and hood. I only modified the drivers seat riser. Hope this helps some.

So if I understand correctly, the modification of the new riser will require to cut the vertical sheet metal and then reweld, correct? Anything else?

Is there a writeup thread for this? I looked but may have to try again.

Thanks.

 

1971 M-code Mach 1

The vertical is too tall on the new seat riser. All I did was cut it down to the height I wanted then welded it down to the floor pan with a few 1 " stitch welds around the perimeter. Once I cut the riser down I lost the bottom 90 degree flange that you would usually plug weld down. You can always take the time to weld the flange back on, but I didn't think it was necessary. If welded properly, that riser isn't going anywhere when you are done! It takes some trimming and grinding to get it to fit perfect, but nothing too crazy. Just take your time. I also moved mine back about 2-3 inches for a little more leg room while driving.

Kevin
1971 Mach 1

408C Stroker - C4 w/3,000 stall - 8.8" Rear w/3.73's - Disc brakes all way around.

 

 

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Just take your time. I also moved mine back about 2-3 inches for a little more leg room while driving.

 

 

+1 on the moved back 2-3 inches. Did the same thing and I am so glad that I did!

Nothing like lounging in the back seat while driving the car!

Seriously though, the extra couple of clicks made a huge difference in stretching out.

Something to consider.

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Nothing constructive to add, but I always enjoy the thrill of discovering new things about my cars. Sometimes there are happy discoveries, sometimes not so much.

 

At least yours were welded in. The previous owner of my car filled in every crevice with expanding foam and then pop riveted aluminum sheet over the rust. With lots of RTV. Go figure...

Matt

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If your putting in full length pans on both sides, just cut out the old pans and seat risers. If they overlapped the seat riser it may be pretty difficult to get them apart. But it would be easier to try to separate them on your work bench. If you cant get them apart just bite the bullet and buy the new seat risers and cut them down to fit you. Its not too hard to do and you can cut them as much or as little as you like to get a custom fit for yourself. I left my replacement passenger side seat riser alone because my wife is pretty short and it helped her see over the dash and hood. I only modified the drivers seat riser. Hope this helps some.

So if I understand correctly, the modification of the new riser will require to cut the vertical sheet metal and then reweld, correct? Anything else?

Is there a writeup thread for this? I looked but may have to try again.

Thanks.

 

1971 M-code Mach 1

The vertical is too tall on the new seat riser. All I did was cut it down to the height I wanted then welded it down to the floor pan with a few 1 " stitch welds around the perimeter. Once I cut the riser down I lost the bottom 90 degree flange that you would usually plug weld down. You can always take the time to weld the flange back on, but I didn't think it was necessary. If welded properly, that riser isn't going anywhere when you are done! It takes some trimming and grinding to get it to fit perfect, but nothing too crazy. Just take your time. I also moved mine back about 2-3 inches for a little more leg room while driving.

 

From what I read the new risers sit about 1/2" taller, is this the case? If so, may not matter since I am 5'8".

20160929_171923_edit2_small.jpg

 

1971 M-Code Mach 1 w/Ram Air, 408 stroker, 285/291 0.558" roller cam, Blue Thunder intake, TKO600, Hooker headers with electric cut-offs, FiTech EFI w/ RobBMC PowerSurge pump

Strange center section with Truetrac, 3.5 gear and 31 spline axles, 4-wheel disc brakes

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From what I read the new risers sit about 1/2" taller, is this the case? If so, may not matter since I am 5'8".

 

The '71-73s were built around a 5' 10" person (or so I've heard), so you may be OK with the coupe platforms, especially if you feel too low in the car as it is now.

 

I'm 5' 10" myself, and I wouldn't touch a thing. But then again...it was designed for someone 5' 10"...so...

 

-Kurt

satellite-valiant-mustang-license-tags-signature.png

How to buy a '71-73 Mustang:

Rule #1: Assume all classic car sellers are guilty until proven innocent.

Rule #2: No classic car dealer is ever innocent; thus, they are all guilty.

Rule #3: Buy from trustworthy people: Fellow forum members. Visit 7173Mustang's For Sale forum.

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If I remember right,they are more than a 1/2" taller. But not 100% sure. Order one for driver side and set it in there with the seat and try it out. See how it feels. I am just over 6' tall and my head was rubbing the roof. I had to slouch down when driving until I cut them down to fit me. Also if you have new seat cushions and covers it really magnifies the problem by raising you up even more.

Kevin
1971 Mach 1

408C Stroker - C4 w/3,000 stall - 8.8" Rear w/3.73's - Disc brakes all way around.

 

 

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