I just noticed small black stains on my ragtop. The spots are see throuugh in the middle with a black ring around it. I bought some "bluemagic ragtop cleaner" but tried it and doesn't work to well. Any one know of any other MORE aggresive way to take these suckers out ?? And please don't tell me to click the learn button because I did and it says how to clean it but not remove any spots.