I've noticed that every older or "classic" car I've owned over the years has dull taillight lenses.
In the past I've tried:
- Chrome Polish- NOT friendly to many plastics!
- Toothpaste- Works, but a PITA. And you still need to polish somehow.
- Meguiar's Plast-X- My favorite of the available chemicals. This is what it's made for!
I pulled the lenses off the left side and gave them a quick scrub in the sink with hand soap and an old toothbrush. The insides were a bit dusty, but not bad at all. I was then able to examine them a little closer... The red sections of the corner lenses were far more oxidized than the yellow or clear sections. I'd noticed a similar thing on my old VW bus too.
I installed my white diamond wheel on the lathe, and loaded it up with white diamond compound. I buffed the outside of the lenses including the black trim and the edges. It only took a couple of minutes buffing to get the shine I wanted. What a huge improvement!
I then installed my wax buffing wheel and waxed the surfaces. While this wax won't provide a lot of protection, it does do a final polishing of the plastic. These lenses gleamed.
I installed the lenses on the car, turned my lights on, and took a picture. You can see a huge difference! After this pic I did the other side too. Much better! No more dull, dim tail lights!