Well they did change with the Hucks to Bendix, but it didn't have anything to do with that. In '51 Chevy dropped the rear bumper as standard equipment and touted that you could now "drop the tailgate down completely so you can back up flush to a loading dock." I would imagine it had more to do with lower production costs. The old style slide out spare carrier stuck out a little in the back, so the re-designed swing out type was introduce. They also redesigned the rear taillight bracket so it mounted on the front of the rear stake pocket,allowing a completely flat rear surface with the tailgate down. It's not like the repros available today.
Bob
