727 Build for Mid-10s

Got another question for you guys.

Since my trans in a '68 model year, I need to get a 71+ pump support/stator in order to use an aftermarket billet steel front drum. Are there any other parts that I need to change in order to use the wider-bushing style front drum? I've been told the rear clutch piston retainer needs to be either replaced with a 71+ unit, or machined down to to work with the 71+ pump support/stator.