I have a broken 96 580 ext powder special. One of the pistons blew. I am a good mechanic but have never worked on snowmobiles. The bolts, water pump, oil pump, and everything is taken off the case except the stator and the wheel. Is this wheel the clutch? Do I need to take it or the stator off to pull the cases apart? I have new pistons and a new used cylinder. I'm pulling the cases apart to clean and inspect. Is their anything else I should do? Thanks alot