Andy, I have seen a few threads where folks state the tips are welded to the back section of the exhaust and cannot be replaced on their own. I stand to be corrected if someone has done this and would like to know if it is possible as well, regardless of effort as I have a lot of time available currently
I have tried using a Dremel and various polishing bits I have but the actual lips that are rolled were pitted when I got the car and without grinding these down I can't get a perfect finish on them. I did clean and polish the exhaust boxes last time though for something to waste an hour