It can be done with time and patience.

You will need several different grits of sandpaper ranging from like 400 to 6000 grit. Most auto parts stores only carry up to 2000 but if you locate a autobody supply center you can find papers much finer. I used 400, 800, 1000, 1500, 2000, 2400, 3600, 6000.
You will need some masking tape if you don't want to remove the lenses the way I did.
You need some water and a sponge to wipe off what you have been sanding.
You will also need a good polishing compound. I simply used turtle wax polishing compound found in the green/white container and I had good results.

1)tape off around the lenses so you don't sand any paint off your body or just do it the long way and remove the headlight housings from the car.

2)start by sanding the lens completely with the roughest paper first which I started out with 400 grit. Sand in one direction. I went side to side, left to right. Wipe away with the watered sponge. The lens will look very cloudy and dull. Do not be alarmed as this is normal.

3)once the first sanding has been done, go to the next sandpaper grit which in my case was 800 grit. Each time you complete the surface with one grit, you will go to the next grit paper number. Each grit will take away the sanding scrathes from the previous sanding. Simply make sure you are using water along with each sanding. Wet sand the surface for good results when using the finer grits like from 1000 grit and higher.

4)Grab your polishing rag and start buffing the lens with your polishing compound. There are some companys that supply cleaners like Meguires PlastX but I used Turtle Wax polishing compound and had good results.

5)One extra step is the application of an anti-static cream. This reduces the lenses tendency to maintain a static charge that attracts dirt and grit that can, in turn, scratch the surface.

6)your all done and can see the clearness of the lenses.

These photos were taken with a 1.3 megapixel camera phone so the results are even actually better than what you see.

Do this at your own risk, I can't be responsible for any damages.

Thanks,
-RJ

<img src="http://www.xtremecompacts.com/audi/05300612051.jpg">
You can see my refection of me holding my camera phone along with the brick wall behind me afterwards
<img src="http://www.xtremecompacts.com/audi/05300613291.jpg">

 

If you sand through the clearcoat, you need to sand it all off, and have them clear coated again. They will scratch really easily without the coat.

 

in my case, I couldn't spend $600+ per each lens to replace.

 

still look good? Mine look terrible, there's a rock pit near my house and everyday on the interstate I get blasted with debris. I like your write up, thanks for the details.

 

I used a similar process to SporTTY 2-3 years ago... did not re-apply clearcoat - all is well.

 

I bought two "late model" xenon headlight units (2003 and 2004) from ebay.de, for 100 EUR a piece.

 

Thanks for posting that

 

That 6000 grain...does that come in rolls of "quilted extra soft"?

 

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works for haze but does it work for very noticable scratches and nicks?