Recently I was cleaning the inside of my cup from a brown stain left my cold coffee. I use a Mr. Clean eraser, the one they advertise for finger prints etc. Had a idea and went out side to clean one of my classics white walls and it cleaned up with a simple rum of the wet eraser, normally I spend a lot of time wet sanding the wide whites. Then I went to the raised lettering on my daily driver, fronts the worst, simple rub with the ereaser and a wipe with a dry rag made them better then the first day a owned them, this just a hint and makes life a little easier.