When reassembling remember on most of the current OS mufflers of that type the tailcone is threaded. The long bolt must be tightened while the tailcone is being held in the proper orientation of the angled tail outlet. Only then is the external nut tightened, its purpose is to serve as a jam nut aginst the tailcone threads. If the long bolt is not tightened first before the nut is tightened then this is the chief reason for the loss of the tailcone.

John