Looks like your brother just bought a new amp. I use lacquer thinner on plastic laminate at work, and that usually makes scratches disappear on a lot of plastic finishes. Don't know what kind of finish they put on those things. Could be some kind of plastic spray, and you may end up taking the finish/logo off. however, lacquer thinner isn't that strong. Just don't drink it.
Mediocre Bass Club #745
Fender Precision Bass Club #817