If you don't use the disposable plastic film protectors mentioned earlier, I would recommend Novus plastic polishing system for scratch removal. Novus 2 should do the trick.
my mum did mine, and i noticed that there was alot of dirt underneath, so i HAD to get it off lol, she got a needle and put it under the thick black border. but it made a dent on the unit border, but if i put it on again, after cleaning it, then it wont show lol