A bodyshop man told me about this. I wet sanded the lights with 1500 grit paper. After I got through, I noticed that the lenses were much clearer when wet, but hazed up immediately when you dried them off. He told me not to worry, just spray them with clear and it would take care of the haze and keep the yellow from coming back. It worked great. Do they look as nice as the brand new ones on my Crown Vic? No. Do they look great compared to the way they were? Definitely.
Total cost : $8.00 and some change from Advance Auto Parts