I replaced my bearing two years ago at the yard they used a hydrolic press to push the bearing out and by removing the prop the bearing slide off and the new one went in. I heard that you should remove the shaft to check it. But after replacing the bearing have had no excessive wear. The job was 180$ so even if the bearing lasts 5 years I think its worth it with out removing the shaft which is a PAIN in the @$$. Dropping the rudder is the easy part but the taking the shaft out of the coupler on the engine i heard was really hard. It usually has to be cut out. Anyways that's my 2 cents.
1979 Catalina 27 Tall Rig
Day sailor on the