Don't even bother with painting it, IMO...
See if you can find a local custom motorcycle or parts place, that will powdercoat the amp for you. Usually it's for a small fee, but the results are extremely well worth it. Unlike paint, you never have to worry about a powdercoated finish chipping or flaking...unless you dump it in acid //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif