Generally what I do with the tailites is make my black basecoat much more opaque by adding clear binders to it,which means it doesnt hide as well and would take many coats to get coverage,and I start spraying the tail lites with this paint after sanding the lights with 600 and then a gray scuff pad..when I feel I have achieved the look I want ,or the customer wants then I stop coating the lights and then clear them....they wind up looking like a million bucks and you can still see through them when you hit the brakes.....Of course this same process could only be achieved with the headlamp if the lens is made of plastic,cause the paint isnt gonna stick to glass,then the other 2 things to be worried about is if you do this the outside of the light lens,the stone chips and bugs will probally reek havoc on it,so it would be great to do it from the inside ,but then I dont know if the heat would be an issue.....definately worth a try....however I am trying to get my stock light brighter,have no clue why you would want to tint it and get less visibility out of it then it allready has,but then as the years go by ...so does my sight get worse...........hope any of this helped