Fiero Folk,
I have two sets of '88 GT tail lights -- three if you count the ones on my car -- I've been wet sanding with 2000 grit sandpaper on and off throughout the pandemic. Actually, I've only been sanding one lens with "TIAC".
It still look hazy and a bit yellow, although it feels very smooth. I am only wet sanding in one direction, inside and out.
I've consulted Pennocks and several "how to refinish your headlights" videos. Will these 30+ year old lenses ever look as clear as those on line or have they just yellowed to much over the decades?