Pictures would help confirm exact tip you're inquiring about (just to be safe) but yes optional 2.5L exhaust tip did just slide over OEM muffler tip. It secured w one Allen screw each side as I recall.
That said, someone may have tacked yours on but you should be able to readily see the dirt dauber's work. AFTER squirting copious amounts of [fka PB] Blaster or Kroil penetrating oil between std and optional tip for a couple of days, try a rubber mallet to jar it loose side to side.
Good luck
