the 1 ive got now luckily aint got any but my old 1 did and it was a never ending fight with it came back all the time i would personally go with the carbon roof skin and just paint it to match your car if its not the look your going for any good trimmers could make you up a ne inner roof lining and from what i hear the carbon is built up to place in to the sunroof hole so no need to try weld a plate in

im actually thinking of doing this before i get any rust lol

there around £480 but you will pay a lot more to keep having the problem sorted