Here is the problem ...
FORD does not give an an ID Chart for 50's transmission usage (49/59 MPC) as it does in the subsequent MPC (1960-1964) so as to actually derive correct service parts. If an earlier than 1957, most likely the drive and driven gear (along with cable housing) are different from a 1957/design.
Good eye on the gear placement (HI - LO) of differing trans. There is also L & R to consider. Let me see if I can nail this down and get back.
http://www.vanpeltsales.com/FH_web/f...ings_trans.htm