In the owner's manual they say to remove the 10mm bolt at the rear of the muffle to remove the baffle for cleaning. I did that and I can't seem to remove it. Has the factory welded it on to prevent owner's like me from messing with it? I was going to try to make it quieter before I jet the carb. Has anyone actually done this? I am thinking I am going to have to grind the weld off to remove it. Anyone?