BradB, in the mid '80's, I knew a guy in N.O. who picked up an early 60's Chevrolet panel that was either 3/4 ton or bigger. No duel wheels. It was Navy surplus. It was used at the navy base in Belle Chase, across the river and south of N.O.
The panel was used to carry some kind of outfit that was described to me as a jet-engine jump-starter. It had all kinds of holes cut in to the sides and top with a bunch of louvres for air flow. All the plumbing was gone from the back but it still had a plate on the dash designating it as a military vehicle. It was battleship grey.
Jacques