I would use automotive paint. The key is to do light coats not heavy,that will make the paint more durable also using a clear coat will help as well. go to an automotive paint shop to get the paint if you have a spray gun for it.
painting guides
http://www.overclock.net/case-mods-g...ng-mirror.html
http://www.overclock.net/case-mods-g...ing-guide.html
painting guides
http://www.overclock.net/case-mods-g...ng-mirror.html
http://www.overclock.net/case-mods-g...ing-guide.html