590474 is a casting number for the case of an early crash box 4-speed (non-synchro, w/ reverse lock-out). These were used from '31 to '47 in the bigger trucks. This particular number is most likely from a later one, near the end of the run.


Curt
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1953 Chevy 6400, 1957 Chevy 2dr Sedan
--"Mediocrity is easy, the good things take time"