1970 duster 340 4spd TIME CAPSULE!

If you find no sheet one of two possibilities exist..One, the original owner found it/them first & put them away for safe keeping or two, there was never one in the car from the beginning which is doubtful due to it being a Hamtramck car. Did you ask his wife if there was a folder perhaps of documents with the car? This senario is not uncommon...hope you find it & good luck with the truck! :-D