I have a 280z that I've been building and I found that it's time for a good old engine rebuild. I pulled the engine and got it all apart exept for the crank shaft. Because I can't seem to get the "rear main bearing" off. I don't want to damage anything so I thought I'd ask so I don't mess anything up. And what I should use to get the blackness off my piston heads or if I should just get new ones. Thanks