I understand you just want an old truck and that's fine. But realize it's a clone or something/someone has added a 1/2 T cab to a 3/4 T or switched VIN plate or title or ?. Anyway you may have EXTREME TROUBLE when registering it.
Further, GMC DID NOT stamp frames. Only Chevy. If you find one, post it.
The marketplace has said that short beds are more desirable, therefore more valuable. There are many who still prefer long beds.
If you could post the numbers on motor, title and VIN plate (if it has a legit one) we could give you a better opinion.
Contrary to the paranoids, there is no danger in posting a VIN number or license plate. Leave the production number off if you want. You say the plate is wrong but you don't really know. Yet.
There is an outside chance that because it's old, back then, some DMV's used different methods of serial numbering. Usually the motor number was used. Motor gets replaced, then it does not match title and/or someone changes to another number, and you are off to the races. Something could have gotten mixed up and it's all legit IF the difference in numbers makes some sense. (outside chance). 1950 and older had hex clutch screws. 51-up, rivets.
