I used a product call Gel-Gloss, available in the bathroom section of either Lowe's or Home Depot, maybe both. I can't remember which one I bought it at. It's used to restore the shine to fiberglass tubs and the like. The corrugated fiberglass on my Granville was getting pretty "furry" in spots when I bought it. I gave it a shot after reading about it. Two applications of it and some wax did a very impressive job. Inexpensive as well.