I have two thing that I need some help with guys. First off, I have a little Poulan 2055. Its just my little trim saw but I am starting to use it more and would like to give it a little pick me up. I have heard of people just doing muffler mods on their saws, but I haven't been able to find anything yet on my saw. I took the muffler off, but I am lost as to where to start gutting out the little muffler if possible at all... My second question is, how hard is it to do a complete top and bottom end rebuild on a Stihl MS290. I am looking for another saw, preferably a stihl, and I have found one that says it has a bottom end knock. My thoughts were rebuilding it if the price is right, but I have never done it before so I thought I would ask. Thanks