Question about fiber wheel liner and trimming

I have 285/70r18 Toyo AT3s. I recently changed from a +18 offset wheel to +12. I’ve noticed a slight rub on the fiber wheel liner (on the side closest to the cab). I don’t have mud flaps. It only appears to be rubbing because the liner isn’t flush with the removable bracket that sits behind it. The tire doesn’t touch the cab mount or even come close to the bracket behind the liner. I’ve seen videos where people remove the bracket and then pin the liner back. However, I’d like to keep the bracket on (my understanding is that it’s purpose is to deflect the front tire in a high speed impact and keep it from entering the cab). It looks like there is already a hole in the front of the bracket that I might be able to successfully use to pin the liner back. However, failing that, is there any reason that I can’t just cut off the small section of liner that the wheel is rubbing? Could that lead to future issue? Something like water intrusion into the frame if there are holes no longer covered by the liner? Has anyone on here pinned or cut back the liner without removing the bracket and could lend me some advice on best methods? Thanks.