just to update:
What you need is 800 grit, 1000 and 2000, high speed buffer and maguire's polish.
1. Sand light with 800 grit. ( wet sand)
2. Sand with 1000 ( wet sand)
3. Sand with 2000 ( wet sand)
Rinse light and dry.
2. onto a fine cotton polisher pad, apply maguire's polish. Use your high rpm rotary buffer / sander with the cotton pad adaptor and polish. Run at around 1500 rpm and make sure you move fairly fast, you do not want to melt a spot and then have to start from scratch. after you finished, rinse, and repeat.
Do this about 3 times.
Last but not least, foam polisher pad. Again , maguire's car polish, and buff, this will remove any fine imperfections.
Lastly, you can apply maguire's car wax via foam disk for rotory sander / polisher, this will seal the new shine and prevent the plastic from yellowing/ dulling.
This works on ALL plastic lights and the finished result is a like NEW clear surface, not just better, but like new! I will post pics after I do my old set to prep them for sale.