Well done...might be better on the car rather than in the house :laughing::scared:
You can go further with 1500, 2000, then 3000 and 6000 trizact pads, will get you almost to final polish by hand stage
If you really want to stick with passive lens then just add lighting indoor or out until you can see. It's mainly the UV that causes the damage, within limits obviously
But as above active helmets are very good and cheap nowadays I wouldn't go back
Try sanding it further but not through the lacquer, if that doesn't shift it, as rainwater often etches paint, then if you feel the need, or the deprssion shows too much, then scotchbrite, sand with 800 the whole panel and re-lacquer.
Keep it out of the rain and free of bugs......fat chance!!
Bought 20 of these when they were on offer at half price
https://www.eurocarparts.com/search/545774311
No complaints they seem to work as well as any I've used before and better than some.
My brother has bought a barbeque which is being delivered wednesday.
http://www.sundaygrill.com/en/gd/prodotti/p97-one-hood.html
The instructions say to use a particular "silicone" based adhesive specially designed for the purpose...
There is a 2k etching clearcoat,
https://www.jawel.co.uk/index.php?main_page=product_info&products_id=4033
https://morelli.co.uk/2k-alloy-self-etch-clear-activator-4-1-mix
22mm copper pipe flattened and folded or you can use a chunk of aluminium from bits of engine ancillary mounts etc.
I've got some about 8mm by 30mm ally bar you can have if you want.