Check out here where i asked him
“Yeah i remember you did that 
and it looks really nice.
If i would want to do something like that, how do you do it? i have a bunch of different wet sand papers from 100 to 8000, would that be enough or do i need some kind of polishing compound to get that shine on clear plastic?”
And he answered.
“cajampa, the high wet-dry papers are the way to get it right up to ready, then flip the sandpaper over and use the paper back with Mothers Billet Aluminum polish. That or a newspaper. Lay it flat on a hard surface such as a glass table and polish away. Use a clean section of newspaper to buff it. Don’t use cloth at all. You’ll be amazed.