Depending on how much the bearing retainer diameter needs to be reduced, it might be a good idea to use Allen bolts instead of hex heads to install the retainer. Less chance of the bolt heads contacting the bellhousing bore.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!