does anyone know if the cabin dimensions remained the same for 37 and 39. specifically, i'm planning to put a 39 split bench seat in a 37. will it fit?

The front seat will exchange OK. The back seat of a 1937 is not as wide as a 1938-39 back seat. The rear wheel tread was wider in 1938 so the wheel wells were pushed out farther making more room for the wider rear seat.

thank you very much Chev Nut for the reply