Long story short: I'm installing a narrow bolt pattern transmission behind a 74 302. The front bearing retainer is smaller than the hole in the bell housing. I understand that the large diameter retainer can be found on a large bolt pattern transmission. What year did the larger retainer began being used?
I believe the narrow bolt pattern, smaller diameter front bearing retainer Toploader is 1964 only, so any bearing retainer from a 1965 thru 1973 Toploader 4 speed should work. Not sure if a retainer from a 3 speed Toploader would work or not. I am assuming that you will be looking for a small (1 1/16" x 10 spline input) retainer.
The 3 speed ('64) Toploader bearing retainer is smaller than a 4 speed ('67) but so is the hole in the bell housing. I tried putting the '67 dual pattern 4 speed in a narrow pattern bell housing ('64) but the hole was too small. The retainer from the 3 speed would not work on the later 4 speed. I think Ford was transitioning from the T-10 to the Toploader at that time? The later model 1 3/8 diameter input shaft retainer and the 1 1/16 one have the same bolt pattern and OD on the retainer itself.
Thanks for the responses. I dropped off the bell housing and transmission at the machine shop an hour before it closed on Monday. Later in a stroke of brilliance I called a Ford guy about 30 miles away and he told me he had what I needed to mate the motor to the trans. I was at the machine shop when they opened on Tuesday to find the two mated, bungs welded in and a spacer fitted to adapt the bearing retainer to the bell housing. That part of the problem solved. Now to get the pilot bushing from Advance Adapters. I am still trying to wrap my head around the fact that the shop owner stayed late to complete the task for me, but then he is a hot rodder.