You see those headlights you pictured. Well, I did a pair on a Cadillac CTS yesterday as a favor to a friend, as one good turn deserves another I figured.
The Headlights you show look like mint condition compared to the pair I did. These were literally white, and the passenger side was at some point restored by God knows who, and God knows what they "coated" the Light with?
Whatever it was, maybe Spar Varnish, it was yellow, and hard as nails.
I got caught with my pants down on this little job, bringing only 1000, 1200,1500 2000 grit papers. I actually needed 400, and the way I got worked, I thought for a second that an angle grinder might've been a better tool!
With the 1000 paper (by hand), and for how long I worked per light, I "saw the light", and conclude for any future headlight restos, I better have some more aggressive papers in my arsenal. I've used papers on the little drill plates (3M?) in the past. They might be faster, but I've messed up once on my own car, running over past the light, and onto the paint with a moment of a lack of concentration, even though the lights were masked well.
After at least a 1/2 hour per light (just wet sanding), I was able to remove about 98% of the damage and coating, then went onto WG Uber Compound, and then Megs 205, using 4" LC HT Pads (Cyan and Orange) on my PC 7424XP with 3.5" Backing Plate. I could still see some really deep etching into the plastic after I was done, these lenses were really beat.
Sorry I have no before, or after pics, but they were much improved. Before, they had to be absolutely useless on the road at night.
What I used as a Sealant-Coating, was some Pinnacle GL Paint Coating, figuring this had to be better than just a simple wax, or sealant.
Some good lessons learned with this one.
Mark