im not sure if you could get to the positive feed that goes to the cig lighter easily as ive never been in a cup, but when i did some on gengars car we had two under seat neons and a boot neon (see his pics in ICE gallery under hon chan) wired into a switch next to the fog light switch. the switch was then fed by a wire coming from an extra circuit we put in for his install, although you could take a feed from any live wire.
you can buy neons that are powered by the ciggy ltr but i think they look tacky; if you can get behind the lighter and find the live wire then simply wire that into your neon and earth it on the ni=egative cig wire. however, this would mean that it would be on all the time that your key is in the ignition position (i think theyre switched?). You might wanna switch it like i did. looks flash if nothing else.
