Nick
The floor pan was received with my ‘46 and mixed in with a bunch of parts. It had that hump. That pan was in bad shape and couldn’t be restored, so it was junked.
I did a quick check my Chevrolet Master Parts Catalogs including editions: 1929-1942, 1929-1946, 1929-1948 and 1929-1950. Oddly, the 1942 edition is the only one that references a floor pan for the 1940, 1/2 ton KC model. It is group number 16.545 Floor Board-Floor Pan, in the ‘29-‘42 catalog.
I have photos I can email you of the pages from each of those editions, if it will help.
Send me a PM with your email address and I’ll get them to you later today.
I’d post them here, but the files will likely be too large given the current website limits.
As you may know, one of the challenges of working on the 1941-1946 models is that civilian vehicle production was essentially curtailed during WW2. After WW2 ended the demand for new vehicles surpassed production capacity and early ‘46 models often were assembled with parts held over from other pre-war models. One example I encountered on my ‘46 restoration was the fuel filler grommet. It came with a leather grommet, but later productions that year used rubber. My guess is the “humped” floor pans might have been used only in the early 1941 models and later models abandoned that design feature? Why it would it have had that feature in the first place? I don’t know. Maybe to prevent “oil canning”??? It doesn’t seem to have been a transmission clearance factor, at least from my experience.
Maybe someone else can help correct or shed some light on this too?
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