My understanding is that only the 54 bedsides (original) had the impression that followed the fender, and 55's had flat bedsides where the fenders mounted, but I may be wrong. Mark has more experience in this area. My thinking is that GM saved some money by not stamping the impressions for the fenders after that one year.
As was stated above, the frame looks like a 47-53 frame with the higher arch over the rear axle. The pictures above look like the cross-sill is a taller one for the earlier bed, which would make the 54 bed sit higher than it should, and the fenders would also be higher.
I think the OP has an apples and oranges situation as far as mounting the bed properly.
Unfortunately, the FAM has NOTHING about the bed assembly and mounting.
Last edited by klhansen; 01/21/2026 4:40 PM.
