Hi, and welcome!
The front end, all the way back to the doors, is standard pickup truck stuff. Rear doors will be the same from 56 to 59, I believe. Is yours in running shape? My 59 Burb is in need of a total restoration, probably an off-the-frame operation, and it will hit the road again with a Cadillac 500 engine, Turbo 400 transmission, and a 3/4-ton independent front suspension to match up with the Dana type 60 positraction rear end it's got already. I'm looking at several years, and several thousand dollars before I get to drive that one again!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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