It is legal under a certain measurement of lumens. No glow in the dark pigmenting (even industrial grade powder for emergency exit sign screen printing) will distribute enough lumens to be regarded as a visual distraction.
In order to become a visual distraction, it would have to hinder another vehicle operators vision. I can't see DOT being against anything that makes any car more visible.
There are as many different tints of glow as colors in the rainbow, some appearing completely clear in daylight. The more pigment powder used, mixed with your solivent and binding agents (in this case, a clear basecoat as commonly used in pearl mid-coats), the more lumens it will distribute.
I don't know the longivity of the powder outdoors, but I have used several in screen printing and other paint applications. You can mix it in with any kind of paint, but a clear over the existing color wanted in daylight works best.
I would also suggest painting the coat in the dark with the material holding a fresh light charge! It goes on clear, but it should be checked constantly durring application for even coating. You aren't concerned with gloss or anything in any basecoat (color) other than desired coverage. In this case, it isn't visible unless the lights are out. Just remember that. And, it looks really awesome when you apply it.
I would also suggest keeping the pressure in the gun down. If you can, use a smaller touch up gun to get into places and to keep from wasting material.
When you get the rest of your automotive paint to do the wheels (or whatever part you are painting) you might ask for a few test spray cards.
As long as you duplicate what you did to the test card with each under coat, glow mid-coat and topocoat, you should have good results.
You might also consider looking into electroluminescent vynil for doing some pinstriping or maybe even factory decals.
You have to bridge gaps (door jambs, etc) with wire and special terminals that attach to the stuff, but it looks pretty cool when you pull it off-
You can also use this stuff in clothing and upholstery.
Living in the future rules.