Since you're going to do the top end, I'll tell you what I discovered on the 951. I found the rings to be difficult to compress by hand while maneuvering the cylinder. The cylinders are also set at an angle which makes it tough to install them with the motor still in the ski That's why I suggest doing the top end with the motor out. Also, its easier to do the pressure test and leak check with the motor on the bench. So, I made some ring compressors out of vinyl siding and small vise grips. I cut the siding into strips approx. 1" wide using a straight edge. Then just wrap them around the piston, bend the ends into tabs, and then use the grips to hold them together. The vinyl is thick enough for the cylinder sleeve to catch it and push it down the piston as the rings go into the bore. After I get the cylinder over both pistons, but before setting it all the way onto the crankcase, I spread a thin layer of threebond between the mating surfaces and the base gasket. That way it doesn't set up on me while I'm dealing with the cylinder, and I don't get threebond on the pistons or the bore. Just a suggestion, but it seemed to work for me.