I bought a '46 in August. Nice truck, no apparent rust...BUT...from research here I have found my cab is a '41! How do I know? It had no rear window but the previous owner had bought a new one from Jim Carter's and gave it to me with new rubber, but it wouldn't fit. It was "missing something". I was lucky to find the pot metal interior frame for it but have not yet installed it.
I suspect my rust free truck is only rust free because it is actually an assemblage of parts from other trucks. When I get it back from rewiring, one of the first things I have to do is check the VIN to see what it says I've got? Did someone transfer the VIN tag from the '46 to the '41 cab? Isn't that illegal? Yeah, I know, "...besides us on this site, who would ever know?". Still, is it really any more a '46 than it is a '41? Is there a VIN stamped someplace on the frame?