[suicideneil]

I've talked to a few guys about this over the last year or so, on this site, BYT & a PC modding site- seems that to get a flat piece of aluminium shinning like a mirror you need to go from 200-500-1000-1500 & maybe even 2000grit, then wet sand with the highest grade before using a proper metal polishing compound & a buffing tool of some sort ( dremel for tight corners ). Several hours of hard work, but being a flat chassis plate makes it easier for sure.