I have 2 year old E60 that has some serious pitting on the windshield and headlight covers. I am about to repair the headlight covers by sanding and polishing as I have done on other vehicles with great success, as they are plastic. My question is this - can anything similar be done to the windshield to polish or improve the pitting on it? It looks as if it's been driven in a sandstorm for about a thousand miles. Thanks.