Yeah, just about anything scratches the body like that. I even thought about taping the flare line and rolling bedliner under it as far as the metal goes, or as far as you can make it go so as not to get the cancer. The bedliner doesn't have to be that thick and can substitute for the gasket. Bottom line, dirt will get behind it no matter what you use, the only way around it is to weld the body and make it a true flare. But even though dirt will get behind the flare, if it is bedliner below it then the flare movement isn't going to scratch anything but bedliner.