Tried this on my parts bike, tab holding arrestor mounting screw collasped. No way was the arrestor seperating from the muffler. Beat it apart with an air hammer, arrestor was intact and complete, muffler had completely fallen apart inside, lots of rust and baffles floating around. If I ever got a new muffler, I would take it apart to see if it actually comes apart as it is supposed to, and replace the screw with a bolt. Would not even try it on your "used" muffler.