Why neons? Have you read anything about cold cathodes? They're brighter, cheaper, smaller, run colder, and use alot less power than neons. They're all around just much better. They come in all the colors Neon comes in.. The only down side they have is their size, they're really small, and they break easily.. But at like $5 a tube, it's not a big deal usually.
4 of them would make your case so bright you could light your room with it. And with a 15a 12v, you could probably run about 150 of them..
