You do not have to use a kit. Start with barkeepers friend. Make a paste rub with a soft cloth,wait until it dries wipe off. do it a second or third time . Then go to Griot's plastic pollish. Unless the headlights are really bad they should clean up.
I've used Mother's resto kit with excellent results. The kit also includes sandpaper if your lenses are really bad, lens polish, and a round foam polisher that you can drop in a drill.
I tried lens repair kits off the shelf, even used the drill buffing wheel, seemed to help and first but the fogginess returned. Have you found permanent results with your techniques?
My understanding is that the plastic covers have a protective coating which is removed by extreme polishing and certainly sanding, which might account for faster subsequent deterioration.
Consumers Report did an item on this last year. http://www.consumerreports.org/cro/headlight-restoration-kits/buying-guide.htm I bought the Sylvania kit based on their testing. It was on my 1996 318i with some pretty foggy lenses. They came out really nice and for the money it was perfect.
I read on another forum that after you perform the restoration, mix equal parts of unscented mineral oil and spar varnish. Dip in a 'shop towel' (get them at Auto Zone, Advance, etc.) and slowly wipe it over the lens. I'm planning on trying it on my daughter's Jetta as it seems they need the restoration almost once a year. If anyone is interested, I can post results.
Ok! Will try it out once we get some warmer weather here in North Carolina. I live south of Charlotte and the weather here has been pretty crappy the last few weekends: cold, snow and then rain this weekend! I'll be using the headlight restoration kit from Mother's. It has the sandpaper mounted on small foam sponges and the polishing can be removed for cleaning. The spar varnish I'll prob get from Lowe's or Home Depot.
I used the 3M headlight restoration kit and was happy with the results, but since it it the only one I've used I can't compare it to others. It has sandpaper, polish, polishing pad and a drill adapter. My headlights and fog lights were quite pitted and after using the restoration kit I put 3MLightguard headlight covers on the headlights and fog lights. Gee this is starting to sound like a 3M commercial, I have no connection to 3M or ClearMask for that matter. I ordered them as a pre-cut kit from here: http://clearmask.com/lightgard.php I only installed the headlight covers about 3 months ago so I can't say how durable they are or how they will resist yellowing. It may be my wishful thinking but the pitting does not seem as noticeable after putting the covers on.
Consumers Reports says Sylvania Headlight Restoration Kit. I used it on my 318i a couple of years ago and was great (up until Storm Sandy flooded the car). http://www.consumerreports.org/cro/headlight-restoration-kits/buying-guide.htm
You do not need a kit of any kind. Try Bar Keepers Friend. Make a paste, rub it on wipe off repeat as necessary. My car is 11 years old headlights look as good as when they were new. A coat or two of Wet Paint over the lights and they will become bug proof. As will your windshield. Bluewagon
... however, you'll be there for a long, long time. Barkeeper's Friend is even less abrasive than Bon-Ami. You might want to check out http://headlightrestoration.org/article-diy.html. Yes, there's an organization devoted to this particular issue!
