what miles is your car done and is the exhaust still one peice from cat back. to remove them you have to drop rear subframe or cut them off. if its high miles and still one peice chances are its stainless cos i doubt it would last 100k if it wasnt. also ford claimed it was stanless and judging by the fact its build through the subframe and a massive job to remove i dont think they intended it to rot. replacments are usually 2 peice