I have a 51 1-ton and put a half-ton bumper in place of the rusty 1-ton unit for about ten years until I got some extra money and had the 1-ton bumper rechromed. Either one fit the same holes in the brackets, though IIRC they are slotted on mine.
1951 3800 1-ton "Earning its keep from the get-go" In the DITY Gallery 1962 261 (w/cam, Fenton headers, 2 carbs, MSD ign.), SM420 & Brown-Lipe 6231A 3spd aux. trans, stock axles & brakes. Owned since 1971.