| In NE. they prohibit any colors that may be used by emergency vehicles such as red, yellow, and blue.  And the neon tubes must not be visible - in other words you have to install them so that the tubes are hidden behind a frame rail etc. (which is the proper way - I cant stand it when you can see the damn tubes).  
 In most states the laws are very vague - its another one of those laws that leaves the door open for officers to pull you over - like an excessive noise/exhaust ordinance.  Do yourself a favor and install whatever neons you like - and only use them when the car is parked - for show purposes - as they were intended.
 
				__________________Nelson
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