As I discovered when deciding what to do with a grooved crank pulley and rear crank surface, Marlin is no fan of sleeves. He says don't use them for those purposes. I'll bet that attitude extends to tranny input shafts.

His reasoning was/is that sleeves are difficult to install straight, and even if you manage to do so, they are too hard. Seals can't wear a (very minor) groove into them to mate well. The seals just wear down and fail.

Ted (Engnbldr) likes sleeves for cranks. Both are good people, but with differing opinions on the matter.

If you try a sleeve, please post how it works out.