Just did mine wasn't too bad.There is a vid on utube that is a pretty good guide. I wound up replacing , the mech seal, the oil seal, the metal bearing, two cir clips and the two orings for the elbow. You need the gasket also. I used a little makeshift press. as shown in the video , to press the bearing in. Also I had to buy Yamalube #4 to seal the mech seal. I used electical tape and oil to make sure the threads on the bolt did not scratch the oil seal.....Important not to bugger up seal. good luck. If you don't have the shop manual and parts list, do download them. Very helpful info in them.