Ive used paint thinner or was it laquer thinner. It really works and wont harm your paint as long as you got a good amount of shiny clearcoat. I do this when everything else wont work. Yes, it needs a good wipe with water or with soap afterwards. Best thing to remove hard water spots on your sunroof I use high acid but very carefully and quickly. I learned and do these tips from pro detailers around here.
