From what little Ive seen, the 48-49ish and earlier use the sliding bracket type, and the later 50? and newer used the swing down type. I say this because my 41 has the slide down type as well as a decrepit 48 panel sitting in my yard. I also have a spare frame off of a 52-53 with the swing down type. Maybe it changed when they went from hucks to bendix?
As far as the big trucks go, can you imagine holding 80 pounds of tire and wheel up to lock it underneath the truck? The rims arent to bad, but the tires are HEAVY!
Jeff
