Don't even bother cleaning.
Pick up some Testor's Flourescent Model Paint, in a color (or colors, mixed) of your choice, and reapply with a brighter, more vivid color. Works a lot better, and is more durable.
And if you have other guns, you can use it there.
I've found that bright orange (a mix of white, red, and yello) and an almost chartruese (green, yellow and white -- mostly white) works great!
The last time I shopped for the pain, about 2 years ago, a model shop had a set of 5-6 colors for about $6. Enough to outlast me and my guns, if I keep the bottles tightly sealed.