When the loader at a quarry tips stone into the bed of my truck, some of the stone hits the rear fender and damages the paint. The ends of the fender are protected by the black plastic mouldings, but the centre around the ball hitch gets damaged. I have the tailgate and side bed protectors, so this is the only part that suffers. Before I get out the rubber mat, scissors and glue, is there a good product that anyone can recommend for this purpose? Thanks. Nick.