Yes I am embarrassed, but thought this might help someone else. I bought a very clean 1998 E300 from a gentleman in the SF bay area 6 months ago and upon closer inspection found that all four headlight covers seemed to be weathered and possibly dirty on the inside of each cover.
After checking the inside on the drivers side and finding it clean and almost sterile inside, I started cleaning the outside with some plastic polish and a soft rag. Twenty minutes into this I came to the conclusion that this was not weather damage and was not on the inside of cover, but was nothing more than spray on detailer (wax) at which point I swiched from plastic polish to 2 cycle gasoline (all I had).
It took an hour or so but now I have almost crystal clear headlights (need a little more work) and just a little embarrassment, dumb, dumb, dumb.
This is a little out of context for this forum, but hey, this is my favorite place.
Paul


1998 E300