The font is the SRT font, so I figured it would go with the Jeeps, though maybe SRT is more for the road...
In terms of colors, you have the perfect vehicle, since most would pop off white. I have to look into producing these, but it would be better to come up with a universal color scheme so that we do not have to send out a lot of different files (usually printing places charge a setup fee, unless they get printed digitally).
I can come up with other options for the fonts, and in terms of colors, are people going to stick them on the body or the windows?