Pin box hitting bed rail

I have the exact same trailer and the exact same problem. I have not actually hit the bed rails because my tonneau cover rails are mounted inside the bed. I have raked that fiberglass cover against those rails quite a few times so much so that some of the mounting screws holding the cover on have ripped out. I have thought about just trimming the cover a little higher to give me some more turning radius but I have not done it yet. I have adjusted my backing and turning skills so as not to "crunch" it anymore. Love the trailer though....just finished a 7 week out west trip!