We have Winn MH, the style with decals (not full body paint - I wish...) No matter what I try to use to clean I can't get grey grunge to clean away from white fiberglass areas, it's like it is unde...
Maybe a little bathroom mildew remove? Did someone wax the decals and it's mildew under the wax? If so, wax would have to be removed first and then bleach water or mildew remover.