I would have to research it to be sure, but in the early years of the new style '60-'66 Chev/GMC trucks, there were some different labeling going on to what we are used to in the later years. I believe I recall some "2-Ton" looking trucks labeled as a 3500 in the early years. They also made a Chevy C-40 for the first 3 years that looked like a "1-Ton" cab.
I would say that what he has is original and correct, but as mentioned, I would need to verify it to be sure.
Bill
