Trunk Floor, Tail Panel, Quarter Panels, Outer wheel wells - Order of importance?

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I'm ready to tackle my trunk floor, tail panel, wheel wells and also the quarters.  My questions are this:  Is there a certain order that I should do this in?  I'm guessing it might be easier to do the trunk floor if I have the quarters and tail panel cut out first?  Or is that wrong and I should do one before the other?  

Also I currently have the car up on 6 ton jack stands.  The rear are under the axle and the front the frame rails.  Can I do all this work with the car the way it sits?  I do have a rotisserie but I did read plenty of posts on here saying NOT to do this type of work on a rotisserie.

 

Mister 4x4

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You're fine, and correct not to do it on a rotisserie.  You want the frame rails and suspension to take the weight of the car (as normal) because supporting it by the frame rails could cause something to tweak irregularly. The unibody structure has the "B/C-pillar" solidly attached to the inner wheel houses and rear frame rail, which is huge for the structural integrity.

I pulled my taillight panel then the trunk pan & drop-offs.  Then I welded a cross-beam between the frame rails just ahead of the rear cross member before removing and replacing the rear cross-member.  After that, I replaced the trunk pan and drop-offs.  Then, I replaced the taillight panel, but didn't reattach to the quarters.  Next came the quarters and outer wheel houses (did each side separately).  My logic was that having something major attached while doing each area would help maintain the integrity of the car's unibody - which I was honestly waiting for the whole thing to collapse once I pulled the taillight panel... it didn't.

I've also seen others pull all of those pieces with no issues whatsoever.

Another valuable tip I received was to clean out and treat the insides of the frame rails after the trunk pan's out - you're never going to get back in there and have another chance to do this.  Just a little extra insurance policy for the insides of the frame rails.

Hope this helps!

 
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I pulled my taillight panel then the trunk pan & drop-offs.  Then I welded a cross-beam between the frame rails just ahead of the rear cross member before removing and replacing the rear cross-member.  After that, I replaced the trunk pan and drop-offs.  Then, I replaced the taillight panel, but didn't reattach to the quarters.  Next came the quarters and outer wheel houses (did each side separately).  My logic was that having something major attached while doing each area would help maintain the integrity of the car's unibody - which I was honestly waiting for the whole thing to collapse once I pulled the taillight panel... it didn't.
Was this cross-beam the thing you mentioned in your build as the "gas tank hammock"?  If my cross member is in good enough shape and I can leave that will I still need this cross-beam temporarily between the frame rails?

 
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When I did mine, I just had it on tires and sitting as normal on the ground. I cut out the tail panel, half of my trunk pan was already gone, so I finished cutting the trunk pan, drop-offs and the rear cross member out, Cleaned and did some rust prevention on the inside of the frame rails. After welding in a new rear cross member, trunk pan, and tail panel I moved to the inside and did some repair work on the floors. I went back and cut the quarter panels off and did one side at a time and at the same time, repaired the outer wheel houses and welded in new trunk drop offs.

Every so often, I would just shift gears to another part of the car so that I wouldn't get frustrated on one certain area. Rebuilt the door hinges, realigned the doors and now working on the front end area.

Tom

 
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So really as long as I'm supporting the car by the rear axle and the front by the suspension that would mimic it being on all four tires. As long as the car is level I should be good to go right? I'd just prefer to keep it on the 6 ton jacks to have that extra working height and more room under the car.

 
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Do this. Cheap (scrap lumber), easy, much safer than jack stands, keeps the weight on the suspension, and plenty of room to work under the car. I did an FMX to T5 swap with these no problem. Just some 2x12 from the scrap bin at menards and a couple pieces of 2x4 and nails.



 
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I'm not qualified to get into bodywork stuff, but my "logic" would say to measure everything before cutting anything as long as it's all straight, not crashed and damaged.  That way you have a reference to go back to.

Geoff.

 
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Do this. Cheap (scrap lumber), easy, much safer than jack stands, keeps the weight on the suspension, and plenty of room to work under the car. I did an FMX to T5 swap with these no problem.  Just some 2x12 from the scrap bin at menards and a couple pieces of 2x4 and nails.

Good idea Jason!! Thinking out of the (scrap) box!!

 
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Do this. Cheap (scrap lumber), easy, much safer than jack stands, keeps the weight on the suspension, and plenty of room to work under the car. I did an FMX to T5 swap with these no problem.  Just some 2x12 from the scrap bin at menards and a couple pieces of 2x4 and nails.

Not a bad idea...  Looks like you stacked about 8 of those for a 16" lift?  What length did you cut them at?  About 20 inches?

 
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8 pieces on each for 1 12" lift. I cut them about 18". I think 20 would have ben better. I just used framing nailer to nail them together each layer.

 

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I pulled my taillight panel then the trunk pan & drop-offs.  Then I welded a cross-beam between the frame rails just ahead of the rear cross member before removing and replacing the rear cross-member.  After that, I replaced the trunk pan and drop-offs.  Then, I replaced the taillight panel, but didn't reattach to the quarters.  Next came the quarters and outer wheel houses (did each side separately).  My logic was that having something major attached while doing each area would help maintain the integrity of the car's unibody - which I was honestly waiting for the whole thing to collapse once I pulled the taillight panel... it didn't.
Was this cross-beam the thing you mentioned in your build as the "gas tank hammock"?  If my cross member is in good enough shape and I can leave that will I still need this cross-beam temporarily between the frame rails?
Exactly right.  I used it because it was the most handy piece of metal I had laying around at the time that would fit all the way across.  Since the rear frame rails were going to be separated from pretty much everything at the rear end, I figured I'd at least give them a little bit of support (from each other) while I replaced the rear cross member.  If your cross member is good, you won't need the extra bracing - I just used it for peace of mind while having it all apart.

BTW - the gas tank hammock was not actually part of my build, but rather a Redneck Engineered solution to keep the gas tank in the car since the previous owners had let the trunk pan rust out so badly it fell apart (since the forward bracket for the gas tank straps welded directly to the underside of the trunk pan, after all).

As I found it, once I started pulling loose trunk pan sheet metal from the car:

trunk1.jpg


While employed as a support bracket while I replaced the rear cross-member:

rearend1.jpg


Rear cross-member replaced:

rearend2.jpg


While I had it all open, I treated the insides of the frame rails with Rust Bullet Black Shell (epoxy primer):

trunk1-1.jpg


Make sure to get the 'long' trunk pan, not the short one like I did:

trunk2-1.jpg


Since mine's a restomod and I'd already bought the short panel (not knowing there was a difference), I just made a panel to bridge the gap:

trunk3.jpg


Just after removing and replacing that rusted out quarter extension panel (whatever it's called - seen in the other pics):

rearcorner1.jpg


After that, welded in the new taillight panel:

taillight1-1024x768.jpg


And test-fitted everything to see that I'd gotten it all lined up:

taillight3.jpg


After that, I started in on the quarters.

Hope this helps!

 
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Regarding floor pan and drop offs.

How one is supposed to handle the corner between the two? I saw on few occasions the floor pan sheet folded to rest onto them. (Mine is straight)

And seen drop off with a 90deg bend on the top. What is the expected construction from factory?

 

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Regarding floor pan and drop offs.

How one is supposed to handle the corner between the two? I saw on few occasions the floor pan sheet folded to rest onto them. (Mine is straight)

And seen drop off with a 90deg bend on the top. What is the expected construction from factory?
Both the repop trunk pan and drop-offs had 90 degree bends for the frame rails. I'd already done the trunk pan, so I just laid mine over the top of the trunk pan on either side.







 
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Do this. Cheap (scrap lumber), easy, much safer than jack stands, keeps the weight on the suspension, and plenty of room to work under the car. I did an FMX to T5 swap with these no problem.  Just some 2x12 from the scrap bin at menards and a couple pieces of 2x4 and nails. 
OK, here is my version going off your idea and also others I saw on YouTube after you piqued my interest.  Should give me about a 12" lift from the bottom of the tires.



 
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Both the repop trunk pan and drop-offs had 90 degree bends for the frame rails.  I'd already done the trunk pan, so I just laid mine over the top of the trunk pan on either side.
Downloaded and saved these picts, thx for posting them.

You ment like this? 

Is it assembled like this from origin or were the drop offs somehow folded and one with the floorpan?

Meaning is there a need to keep some of the old floor metal (+- 1 inch) to do this if the drop offs are ok?



 
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Fabrice, I think the floor pans were a 1 piece design with the drop offs on it and bent 90 degrees! 
I've asked, because when i've patched my 73, having just light corrosion on one side at the fold, I remember there was no double metal there.

@Mr4x4 used new separated sheets that were having the fold. Just like the floor pan that I have with a 90 deg extra bend.



Unless I'd replace the drop offs and buy new ones with a fold on top, I will have to cut the floor +- 1 inch away from the drop offs,

This way, I can spot weld from beneath and also eventually do same from the side once the lower quarter is removed...

Not expecting the 1 mm extra height to be a prob.

Thanks for clarifying that.

 
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