The radiator is a 4 core radiator instead of the much thinner one usually seen. It could be out of a 1-1/2 ton maybe? Or maybe it was an option down in Mexico. I discovered two Coahuila Mexico license plates from the 1950's under the seat yesterday! With the speedometer being in kilometers and the license plates, I think that proves this truck isn't from the US.
What is with the fan shroud in the last photo. Didn't know they were available on older trucks, especially 1/2 ton.
