[R129 SL] woes with plastic windows

[R. A. Foster]

In the last week, I've noticed some dark yellowish and brown discoloring around the corners of the plastic windows in the soft top of my '91 500 SL.  The car is in the desert and basically shielded from the elements by a carport and has been for several years.  This discoloration is new and rapidly unfolding.  I have never used any chemical detergents either on the body of the car or its interior and am at a loss to understand why this is happening; the car has withstood high elevations in temperature just fine, if indeed that is the problem with the plastic windows.  Can anyone suggest a product or procedure that might reverse or at lease retard this discoloration from expanding?  Thanks to all, Bob
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.pairlist.net/pipermail/r129list/attachments/20060724/7b5ae66d/attachment.htm