So I have recently purchased a 92 ski doo 470 mx formula with 330 miles on it and a 98 polaris xcr 600 triple indy with 3500 miles on it. Ive managed to get the ski doo running well but ive run into a road block with the polaris. Tested compression on the polaris and only the middle cylinder has compression. Ive come to the conclusion that it needs a top end rebuild but getting cylinders is difficult. I can get pistons and everything else fairly easily. I havent torn the top end apart yet to see hoe bad the damage is but i saw through the exhaust holes the the pistons are pretty scored. So im assuming the cylinder walls arent the best. Im also a machinist so im wondering what you guys think would be the best route, sell it for parts, bore out the cylinders myself, or buy everything when I have the opportunity to do so. Any help or guidance would be appreciated, Thanks!