Our truck has the plastic OEM headlamps and the lighting was rather poor. Looking at them I could see the yellowing and pitting from years of use from its prior ownership (Oregon lays sand/gravel on the roads for ice/snow conditions). Thus, before dropping +$100 for new headlamps I decided to try my hand at polishing them as that's a cheaper alternative and less costly. The short story: Amazing! Like [almost] new! I highly recommend doing this either yourself or from your local mechanic.

I trust Mothers so I used the product NuLens Headlight Renewal Kit. It has sanding discs in 800grit, 1500grit, 3000grit, and polishing compound & foam ball (the blue half-dome there on the hood). It has enough for two headlights but I found that I was able to effectively use one set of sanding disks on both headlights, thus I have the second set unused for another project. Use whatever you feel good with using.
Not much else to say so here's the pictures
Before:

After:


Before:

After:


Before:

After:


Before (notice the yellow/orange glow):

After (notice the white glow):


I did take pictures of each stage but, meh, it just goes from "holy ****** did I just destroy my lens!?!" to "holy virgin mother of Jesus those look brand-spankin' new!" (really, they look much better in-person )

The biggest hassle were the three headlight aiming nubs on the lens face. Also, I recommend taping the hood line as well (I did that on the other headlight).

After the polishing I saw that the left headlight had some moisture in it and some internal hazing so it's not quite as new looking as the right side -- so it'll eventually need replacing -- but it is still throwing out a lot more light than before! After I polished the headlights I then installed a headlight harness so the headlamps get power directly from the battery. I know it makes a difference but I couldn't really tell inside my messy shop, besides, it was the headlight polishing that made the real improvement.

 

I will be polishing my headlights, when it is warm again.
Mine aren't as yellowed as yours were, because I bought a polishing kit some time ago, but the results weren't as good as yours.
I'm also going to replace the bulbs with a whiter set.

 

Looks good. I need to add that to my "To Do" list.

 

Looks good. I would recommend sealing the lenses to keep them up. I know Meguires makes a UV sealer. I polished mine and then had to do them again about a year later.

 

You are correct. I'm looking for a vinyl lens protector (like I have on my motorcycle) but a sealant may be an easier choice. Thanks for pointing that out as that is part of the job that should be done

 

I watched a youtube video where he used sand paper and wet sanded the headlights. 600 grit to remove the yellow film. It leaves the headlights looking real nasty of course and hazy but no more yellow. Next, wet sand using 3,000 grit. This removes the bulk of the scratches. Next,if you want the max you can polish as you did. Lastly to seal he recommended Rust-Oleum 249117.

Much cheaper than buying a kit and just a run to the local hardware store.My headlights were really,really yellow and dim on my car and figured I'd give it a try.I didn't bother going all the way with the polish just the 600 to 3k grit and the clear coat. That clear sprays super thick fast. First headlight I messed up on haha just wet sanded it off and tried again and went much quicker and lighter coats the next time.The things turned out really nice. I touched up my trucks headlights after too.It works no matter how yellow and bad they look. Just make sure the clear coat if you don't want to have to keep wet sanding every year or so.

 

This is what my mechanic uses and recommends: Gloss is what's needed if there is a choice between shine levels i.e. don't us matte.