I use meguire's Plastx some good stuff... or any polish will work very well with the headlights.

 

^^ I use Plastx as well it does such a great job!

 

Looked for 3M plastic cleaner but only found Mequires (sp?) Plastic Polish/Cleaner--at Kragan.

It took a little bit of an effort, but the stuff worked like a champ--my headlights were very cloudy and now they're like new!

 

on my 05 coupe i get really fine sand paper and very softly rub the dirt off water constantly on the headlight so sand paper will not scrach it then get tertal wax on it and looks like new

 

I use plexus regularly on my headlights/taillights, its both a polish and protectant. If the lenses have that fogged up appearance, you'd probably have to polish them using a pc.

 

I wish I knew about using the Meguiars Scratch-X earlier.
That's certainly easier than using a claybar on the headlights and I am sure it takes about 1/10 of the time.