Bought this ski, owner said it was seized. Couldn't turn the crank so I popped the piston cover off and there was corroded water in there. One piston had been slapping the cover for a while, the cover has a lot of dents and dings in it. I need some advice. What else should I look for? Was thinking of just going ahead and getting a long block. Don't know if I should chance putting a new top end in it or what? I'd appreciate any advice you guys could give me.