You can try distilled white vinegar on hard water spots, i have used it for years. If the spots are not to far gone it could help, and it`s cheap and easy to try. Here is a link to a thread about using it from the AG site. Using Vinegar to remove water spots
The spots are definitely too far gone. I`m in Oregon and the car came from Florida. Long story and a touching one in fact. It looks like it will get published in a magazine. The previous owner left it outside.��
