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
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