I just found a great product for coating the underside of your freashly-
restored fenders, to prevent stone chips and dings. In the States it's
made by Dupli-Color and it's called Truck Bed Coating. It's made for spraying
on truck beds as an abrasion-resistant material and it produces a semi-thick
black textured coating, much like the spray-on undercoatings but much tougher.
I just did my R26 and I'm very pleased with the results.