Carl, I've never seen a short bed 3/4 ton GMC. But GMC made wheelbases of 115", 125 1/4" and 137" in the one ton models from 1946 thru 1950. They dropped the 115" in the one ton in '51, but kept the other two.
How would you tell if the frame was Chevy or GMC?
The front crossmember has a distinctive jog in it towards the front to match up with the front engine mount of the longer GMC inline 6.
