Standard cab, short bed or step side bed trucks from about 64 (or maybe 62, I can't remember which year the body style changed) to the 71 model year fit very well. We did 70 sheet metal onto a 78 short bed frame in a weekend. You need to level the "hump" off the top of the frame above the axle (we just cut it level and welded in a 2" wide piece of 1/8" flat bar stock), then the 70 bed bolted to the 78 frame and you need to change the cab mounts on the frame to match up with the older truck cab cab mounts (We cut the cab mounts off the original 70 frame and welded them to the 78 frame after a bit of trimming)..


The 58-63 standard cab, short bed (or step side bed) will also fit, but the width of the 73-93 tire track will put a pretty tight limit on wheel choice, the outer edge of the tires gets pretty close to the fender lips. Those 58-63 bodies are more narrow then the later 60s bodies, but the large wheel opening on the fenders allows more fudge room for tire clearance.

the 54 - 57 trucks have the same body width as the 58 -63, but the front fenders have smaller wheel openings in the fenders and the wider track of the 73-93 tires doesn't fit very well at all.

Trucks older then 54 have a short nose from the firewall to front grill panel, and the wide tire track make the older cabs more of a challenge. You add fender, hood, or firewall modification into the picture. The 39-47 sheet metal (and older) can work without fenders, but the wider tire track is very apparent, and is hard to deal with on the front end.