I'm a middle school girls basketball coach and after our team won the conference championship this year, the girls suprised me by covering my Element in car paint. It was sweet, but they wrote all over the car, even on the non-window and non-metallic parts. Everything that was written on the lower half, (the non-metallic surface) has been a real struggle to get off. Anybody have any suggestions or home remedies? (besides teaching them to read the bottle before they use it on the car).