[PxTx]

Doesn't sound like the car has been untouched for all of these years so I'm not sure anything would there would be much of a clue. Do you beleive the car is a "Motion" car meaning it ws taken to Joel for work after it's sale from the dealer? I think by 1973 Balwdin Chevrolet changed names- so pretty good chance that it's not a Baldwin Motion car.

I would start by searching previous owners with the VIN in the states you know it had been registerd in. They should get you some clues and maybe even some early pictures. From that you may be able to speculate better.

There are really no consistant true identifiers. Anything which is used as a clue is also dependant upon the time period is was at Motion. For example, Joel's preference on parts to use were certainly different on his 1967 and 68 car than later 1970-72 cars. That is not to even say 1970-72 was consistant.

Assuming it is just a story right now. How was the car supposed to have been prepped by Motion? Small block, big block, hp adders?