IML: Restoring convertible top plastic window; Help needed

[Imp67cc64@xxxxxxx]

 I am working on one of my non-Imperials that has an original convertible top circa 1971.  The top has been folded down and stored in the top well while the hardtop generally remained on.  It is in amazdngly good condition and still fits well. My only problem is the slight, but noticable fading (actually "browning") of the clear plastic window.  Has anyone ever founf a way to restore the clear plastic?  I think I had seen something advertised in JC Whitney years ago, but never needed it and was not convinced that it would work.  I am willing to put some effort into restoring it instead of replacing it as it would be nice to retain the original if I can.

Thanks,
John - Atlanta