Matching Numbers - How many are there?

[GeoBW]

Pulling down my 73 Mach 1 and we found this plate on the radiator bulkhead on the LHS behind the radiator overflow bottle. I presume this is the ID plate for the chassis/body?

Which brings me to my next Q: In a matching numbers car how many different numbers are there to match ... just engine, transmission, body?

 

[GeoBW]

Also, does the 0394 mean it was made early 94, which seems odd?

 

[midlife]

0394 is the rotation number, a designation of where it fit in the assembly line. Parts that were go onto this car also had this designation.

 

[GeoBW]

Thanks Midlife. Do you know how many numbers there are to find on the car?

 

[midlife]

Stamped numbers can be found on the engine, two front fender aprons, transmission, and that's about it. Dashboard and VIN sticker, along with buck tag (which you show) are easily removed and/or replaced (well, the dashboard shouldn't be!!!!).

 

[rackerm]

As Midlife said, the transmission carries the VIN number. I don't know if this is always the case but it is on my '73 H code with a C6. It's on top and can't be seen without removing it. The VIN on the 351C block can be seen using a phone picture or a mirror held behind the top left side of the block just below the head.

 

[rackerm]

Midlife, Does the rotation number on the buck tag always match the rotation number on the build sheet?

 

[jeff8877]

Here are the spots for the VIN on your car...

1.Under top of both fenders in the center...you will need to loosen fender bolts and pull back to see. This is a partial VIN.

2.Dash plate

3.Door data plate on drivers side door

4.Buck tag mounted to radiator frame, can be either side.

5.Stamped on engine on drivers side below head, need mirror to see. Partial VIN

6.On top of transmission, can't see while in car. Partial VIN

7.Build sheet under carpet possibly.

8. Warranty card with aluminum strip in glove box.

Most other parts on the car are stamped with a date code that should proceed the actual build date by up to 60 days in most cases. The key for most people to a numbers matching car is engine, trans and rear end.

 

[midlife]

My recollection is that there are two rotation numbers, depending upon where the car is in the assembly process. One for the basic shell assembly, and another for the outfitting of sheet metal, interior parts, etc. Most rotation numbers seen on buck tags are for the latter part of the assembly.

 

[rackerm]

Which of these two rotation numbers appears on the build sheet?

Thanks.

 

[jeff8877]

Randy,

Thanks for the rotation number info...never heard that before so very interesting.

Maybe we can get Boss1ray to comment here on this...

Rich..can you look on one of your sheet metal parts or how about the rear end tag as it has a rotation number to figure out and let us know?

PS...I really like the aerial pic of your car.

 

[midlife]

My understanding is that it was the latter number, but please don't take these statements as gospel.

 

[rackerm]

Jeff,

Okay. I took pics of my Sept 72 Built 1973 Vert. I have owned the car since 1995. I bought from the original owners family. The car is original with some cosmetic exceptions and it has all the original tags and a readable build sheet.

The VIN and Build date match between the Build sheet and Buck tag, but Rotation numbers are different. The Axle and transmission tags match the build sheet. Based on this and Midlife's post that there are two rotation numbers, it appears that the first basic body shell rotation number is the one used on the build sheet and the second rotation number is what is used on the buck tag for the outfitting of sheet metal, interior parts, etc., just as Midlife stated. From what I have read and seen in pictures, a rotation number was commonly handwritten on the radiator support. It is then possible that the basic body shell rotation number from the build sheet is the one written on the radiator support. I can't confirm this as I have never found a handwritten number on the radiator support on this car.

On the Axle Tag, I see no connection to the VIN, only to the Build Sheet tag number. The engine an carb data tag build dates are within the 60 day build window. I have not pulled the engine or trans on this car and therefore have not been able to confirm the engine and transmission VIN stamping.

Other than your typical date stamps (month/day/shift) on the sheetmetal and part casting numbers, I am not aware of any other things to look for.

Rich

Build Sheet Rotation # = 0978



Buck Tag Rotation # = 666



8 Inch Axle Tag with 930C matching Build Sheet



Engine Data Tag (Early 73 build cars did not have the Engine Decal on the valve cover) I believe the paper decal was used on cars built after March 73.



2100 Carb Data Tag



Inner Fender Apron/Shock Tower VIN



Interesting Valve Cover stampings





free img

 

[jeff8877]

Jeff,

Okay. I took pics of my Sept 72 Built 1973 Vert. I have owned the car since 1995. I bought from the original owners family. The car is original with some cosmetic exceptions and it has all the original tags and a readable build sheet.

The VIN and Build date match between the Build sheet and Buck tag, but Rotation numbers are different. The Axle and transmission tags match the build sheet. Based on this and Midlife's post that there are two rotation numbers, it appears that the first basic body shell rotation number is the one used on the build sheet and the second rotation number is what is used on the buck tag for the outfitting of sheet metal, interior parts, etc., just as Midlife stated. From what I have read and seen in pictures, a rotation number was commonly handwritten on the radiator support. It is then possible that the basic body shell rotation number from the build sheet is the one written on the radiator support. I can't confirm this as I have never found a handwritten number on the radiator support on this car.

On the Axle Tag, I see no connection to the VIN, only to the Build Sheet tag number. The engine an carb data tag build dates are within the 60 day build window. I have not pulled the engine or trans on this car and therefore have not been able to confirm the engine and transmission VIN stamping.

Other than your typical date stamps (month/day/shift) on the sheetmetal and part casting numbers, I am not aware of any other things to look for.

Rich

Build Sheet Rotation # = 0978



Buck Tag Rotation # = 666



8 Inch Axle Tag with 930C matching Build Sheet



Engine Data Tag (Early 73 build cars did not have the Engine Decal on the valve cover) I believe the paper decal was used on cars built after March 73.



2100 Carb Data Tag



Inner Fender Apron/Shock Tower VIN



Interesting Valve Cover stampings





free img

Rich,

Fantastic post! This information should be put in a separate area for future reference. Thanks for the effort.

 

[GeoBW]

Here are the spots for the VIN on your car...

1.Under top of both fenders in the center...you will need to loosen fender bolts and pull back to see. This is a partial VIN.

2.Dash plate

3.Door data plate on drivers side door

4.Buck tag mounted to radiator frame, can be either side.

5.Stamped on engine on drivers side below head, need mirror to see. Partial VIN

6.On top of transmission, can't see while in car. Partial VIN

7.Build sheet under carpet possibly.

8. Warranty card with aluminum strip in glove box.

Most other parts on the car are stamped with a date code that should proceed the actual build date by up to 60 days in most cases. The key for most people to a numbers matching car is engine, trans and rear end.

:thankyouyellow:  Jeff, very comprehensive.

 

[GeoBW]

Jeff,

Okay. I took pics of my Sept 72 Built 1973 Vert. I have owned the car since 1995. I bought from the original owners family. The car is original with some cosmetic exceptions and it has all the original tags and a readable build sheet.

The VIN and Build date match between the Build sheet and Buck tag, but Rotation numbers are different. The Axle and transmission tags match the build sheet. Based on this and Midlife's post that there are two rotation numbers, it appears that the first basic body shell rotation number is the one used on the build sheet and the second rotation number is what is used on the buck tag for the outfitting of sheet metal, interior parts, etc., just as Midlife stated. From what I have read and seen in pictures, a rotation number was commonly handwritten on the radiator support. It is then possible that the basic body shell rotation number from the build sheet is the one written on the radiator support. I can't confirm this as I have never found a handwritten number on the radiator support on this car.

On the Axle Tag, I see no connection to the VIN, only to the Build Sheet tag number. The engine an carb data tag build dates are within the 60 day build window. I have not pulled the engine or trans on this car and therefore have not been able to confirm the engine and transmission VIN stamping.

Other than your typical date stamps (month/day/shift) on the sheetmetal and part casting numbers, I am not aware of any other things to look for.

Rich

Wow, Rich, talk about above and beyond! :goodpost:

 

[Carolina_Mountain_Mustangs]

Here are a couple pictures from my original 73 Mach 1. It was built May 7, 73. The buck tag has lots of stuff on it since this cars has 32 options installed. If you look down at the bottom of radiator support under the build tag you see and 85 would this be the number you are talking about?

It has the paper engine tag on the left valve cover. I do not have pictures of them but there are several inspectors stamps on the engine in a circle, 1/2" - 3/4" dia. with line in middle and a number and probably initials of inspector.

One other thing i have seen hand written on the vehicle and was still done the last time I was in the Assembly plant. They write the number of the car built that day or that shift where the license plate goes. So look behind the rear license plate for a grease pencil hand written number. There was also a sticker there that told the dealer to remove the tie down brackets from the rear of the car. Sticker might be over the hand written number will be may 3 or 4" tall writing.

I do not worry about hiding my VIN# or license plate # there is nothing anyone can do with them and are visible any time anyone views the car. Never understood why some hide them. Is there a reason that I have not heard of??

 

[rackerm]

Thanks David, Question: The "85" on the radiator support does not appear to match the rotation number on the buck tag. Does it match the rotation number on the cars' build sheet?

Thanks again,

Rich

 

[GeoBW]

Thanks David,  Question: The "85" on the radiator support does not appear to match the rotation number on the buck tag. Does it match the rotation number on the cars' build sheet?

Thanks again,

Rich

Hey Rich, while you're on a roll can you diagnose the extra/different codes on my plate below - or is there somewhere we can go to look them up?