Wrote my late '49 off as a typical GM anomaly. Use what was left over on the assembly line and then move on to the new parts for the next year. All in the spirit of saving money? Early...late....don't think it really made that much of a difference. The assembly line used what they had in the bins and get them down the line. Just makes it tough when you are trying to restore a truck to the correct year. Cover one eye and try again.
Tim