[911Freak]

I've used a couple of different process.

Just be careful if you have the anti-glare coating as polishing will remove it immediately

For deep scratches I used 2000 grit wet sanding
then
Polished with a non-grit polishing compound (3M, Maguire's etc)

Then finished it off with a super high gloss carnuba polish, let it dry than buff off, repeated 3X

I used a dremel with a small 2" round polishing wheel I found at an autobody store

I've also used a plastic polish made for motorcycle faring & helmet visors

Proceed with caution

BTW I ruined 1 pair before figuring out this process & using this process polished off the anti-glare coating