The factory did not sit on cases and then use them after the war on 46 production. There were replacement cases made in '41 and so you could possibly have a cases with 41 bottom numbers and a 46 VIN where a dealer replaced bad cases with new cases.
However in this case, the number boss on the 41 case has been ground down and restamped. Further, none of the 46 VIN numbers are factory style with the possible exception of the U & L.
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