Maybe you don't know what door edge moulding is then? Door edge moulding is a skinny vinyl or rubber strip of trim that has a groove in it where you would put it on the edge of your door. That protects the door edge from getting chipped when it's open, or while you're door-dinging someone else. What I'm saying is you could put the trim on the one open edge of the inner fender, right under the tube, which will act as a cushion.