As I said, there is not question. Any radiator out of any 37 Chevrolet truck will fit in your truck. If you are going for the "heaviest duty" radiator, one from a 1-1/2 ton truck is it. If you want less, one of the others might work for you, BUT, the smallest (in thickness) radiator for a 37 truck is a 1/2 ton raditor. The thickest is the 1-1/2 ton radiator.
If you are going to run a 350 or other V-8 behind it, you had better go the custom radiator route. The 37 stock radiators will not cool a a larger engine very well.
