I bought the Miller bushing driver set in 1978. The first reaction shaft bushing I replaced (factory bushing), was too tight, just like you’re experiencing. I avoided them until last fall, when I had to replace one for a friend. It fit perfectly. (Ancient TransStar) I’ve never read any mention of this in any TSB.
Service bushings should never have to be sized. The only exception I am aware of is burnishing the intermediates shaft bushing.
Real good possibility your driver is not setting on the steel backing of the bushing.
Lightly chamfer the leading edge of the bushing and see if that helps.
