I tried everything mentioned above and i finally got the piston and rings into the cylinder. I never could get my set of ex-bore ring compressors to work. I had to install the top ring with a zip tie then remove the zip tie then install the second ring from the bottom and compress it with tiny screwdrivers and the cylinder went on. The set of ring compressors i bought came from ebay and included a piston holder and two piston stops. Has anyone had any luck with this type of ring compressor? The piston doesn't look to have too much wear on the skirt and the cylinder wasn't out of round. I have installed new bearings and crank seals too. Ive had to use parts from several saws to hopefully get a good one.