LeMan,

The cracking in your headlight covers appears to be what is called crazing. It is a series of fine cracks in the surface. It normally happens slowly as the plastics ages. It can also be caused by chemical attack and ultraviolet light. You see it a lot in small airplane windows (which are palstic, not glass) that have sat out in the sun for many years.

Did you happen to use a chemical harmful to plastic in your windshiled washer fluid? For example, I'm pretty sure RainX is bad for plastic.

I hate how new cars today use clear plastic over the refelctor headlights. So many of them craze and yellow as they get old. My '95 Maxima had good old glass prism lens - no problems!

Chip