As stated ease all depends on where the bearing is. Ours is in a strut. It requires that the shaft be pulled out. The shaft clearence with the rudder in is .33 inches so we were lucky we didnt have to have the rudder dropped. Oours came from Buck Algonquin
The part itself is inexpensive and relarted to shaft size. If you are having the shaft removed its a no brainer to replace the bearing no matter how old it is IMHO.