What year(s) and body styles of frames are interchangeable with a '38 Chevy coupe? I assume a '37 coupe for sure. A sedan from these years? A '39 maybe? What about other makes...Pontiac for instance? Is the sedan wheelbase longer than the coupe? Anyone have specifics or a reference source?
All of them are 112.25 inch wheelbase. Pontiac and other GM frames are longer, heavier, and would only work if you changed at the least the front clip to match the frame. You could try an early Motors Auto Repair Manual, a Krause Standard Catalog Of Chevrolet, or some other books, but there's no direct interchange for the frame. It's a matter of what you can fit under there and make work. My book says in 1940 they went to a 113" wheelbase, 1941 116" wheelbase, and 1949 to 115" wheelbase.
99% sure '39 rails are the same, but there's a crossmember or two in there that are different. Might be one of those things where it fits a sedan but not a coupe, or verse-visa.
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