Yeah, its a strange design for sure. There are ways one could do it with just metal, to make a box out of heavy steel, bolts and rivets, then finish off with some wood pieces in the wheel well? I guess not everything made sense even back then.
1946 GMC 1 Ton 1984 GMC 1/2 Ton 1996 Dodge 1/2 Ton 2014 Chevy 1/2 Ton 2020 Ram 1 Ton Cummins