Here are some photos that might help. I’m unable to provide measurements for the fiber board panel without disassembly from my truck. The Master Parts Catalogs, 1929-1942 and 1929-1946, photos shown in the attached, indicate in the parts list, not shown, that these panels were the same for trucks produced from 1939-1946. These references also seem to indicate the retainer hardware was also the same for those years of production.
Last edited by 46Sparky; 03/27/20231:20 PM. Reason: Added comment about the retainers