In Reply to: PTO posted by Theo Morris on August 06, 2018 at 11:07:10:
Do you mean the 9N-733-B housing? The parts books show one, the "B" suffix meaning there was a 2nd revision to the original. Are you certain you have a 1939 9N and going by the serial number? Where did you buy your parts from? Many here use one of a handful of reliable Ford Tractor Parts suppliers like Just8Ns -see LINK.