Hey all, I have a GMS 120 that I have in the nose of a Four Star 120, problem is that I have no muffler. Tower says late July. I can get a Pitts muffler for it, but the motor is mounted upright. My queston is, does anyone know if another muffler will work, or if there is a replacement muffler for this engine? I had a Tower .76 muffler laying around, and it fits the 120 with no problems, bolt holes line up and everything. Will this muffler be too restrictive for the 120? Or will it work. I have not run this engine yet, so I don't know if the .76 muffler will cause problems, don't want to damage anything. Any help appreciated. I hope someone with more engine knowledge than I have will know. Thanks.