Thanks Dave - that explains it - the middle man got in touch finally with the original owner, and he confirms it came out of a 1951 Chevy car (doesn't know the model).
So now please excuse the next question from a rookie, can that car trans. be installed in my 1950 GMC truck.
The total length from front of trans. to back of the torque tube connector sleeve on that 1951 measures 21 1/2" - which looks the same as my truck.
Are there other differences that make the car trans a poor choice for a 1/2 ton ?

Jim