The way for you to get rid of it rubbing the arch on the outside is only by rolling it or by cutting it h=but either way make sure its done properly as if the bare metal is showing you will get rust in no time.
If you get them roled make sure they heat up the paint before they do it as it makes the paint flexible so it won't crack and peel away and,
if you cut it make sure you treat the bare metal like, rust proof it, prime it and paint it and should be no problem.
Hope it helps keeping your pride and joy looking sharp.