Rick - Nothing found in a quick web search for 1941-46 Chevy pickup rear filler panels. I did find and confirm that Chevy offered a rear bumper filler panel for select 1941-46 passenger cars, with this one being offered on ebay - 1941-42 Chevy car rear bumper filler panel to give you an idea of what it looked like.
Someone willing to do some metal-smithing could probably modify that to fit a pickup. But it might be easier to fabricate one, if you or someone has the skills and tools to take that on.
~ Dan 1951 Chevy 3 window 3100 Follow this story in the DITY Gallery "My Grandpa Carl's Truck and How it Became Mine" 1966 Chevelle (Wife's Hot Rod) | 2013 Chevy Silverado (Current daily driver) US Army MSG Retired (1977-1998) | Com Fac Maint Lead Tech Retired (1998-2021)
