Well if you are here on this page, and have a auto with this problem, chances are you are a do-it yourselfer, and don't want to spend any more money than necessary
Here's the problem, these are foggy and yellow, and it's getting pretty dim, I seem to notice a lot of people pulling out in front of me when it's dark out.

You can buy a kit to fix these on the internet for around $25 - $50, or take it to a garage and pay about $100. I opted to do it myself for $15. If you don't have any of the two power tools, a drill, and an orbital DA sander, you can substitute elbow grease, no power tools required. With the two power tools, this project will take just about 45 minutes to complete both lamps.

The yellow haze on these is only on the outside surface of the headlight, so all that has to be done is to remove the outer layer of oxide, and polish. This is no different than buffing out old oxidized paint on the car itself.

The first step is to remove the old oxidized layer. To do this I will used this rotary scotch bright sander that I bought for $5. This one is "Fine" abrasive You don't want to put a lot of pressure on this tool so it digs in and makes a depression, or starts to melt and burn the plastic.
Here is the headlight with the yellow oxide removed. If you don't have a drill, then a scotch bright scouring pad from the kitchen will substitute
Next step, some 400gr wet dry sandpaper, we will use it wet
The headlight after 400gr sanding takes about 5 minutes
Next step sanding with 1000gr Ultra fine again with water
You can start to see it clear up now, after the 1000gr, all of the yellow is gone (takes about 5 minutes)
Next step some rubbing compound, use the heavy not the fine polish (takes about 5 minutes)
The headlight after rubbing compound, it's almost good enough now, but the next step will take it to the crystal clear state
Next the DA sander with a buffing pad, and some liquid ebony. If you don't have the DA, then this can be done by hand with a soft cloth. If you don't have the liquid ebony, and we are only going to use about 1/4tsp. worth. Buy a plastic polish from the car care section in the auto parts store.
Around 5 minutes of final buffing, and the headlight is almost new, crystal clear. The plastic polish is probably a better choice for this step, but I had the Ebony, and did not want to spend the extra $7. The plastic polish will have some UV protection, and it will slow the future oxidation, and yellowing process. It took this car 10 years to get where it was, I doubt I will have it long enough now to worry about any future yellowing.

Before

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