i really doubt it's illegal..But then again loud music and dark tint is illegal..which the majority of the people on this forum have..
any lighting modification is 99% illegal (depending on area) i used to know a county and he told me pretty much anything you do to a car in any way shape or form he could write a ticket for it of course he didnt because he had all the same modifications on his personal vehicle its just a matter of the cop wanting to enforce the shitty laws we have or not... most cops nowadays are too worried about whether you have a basketball goal or not