Ive tinted mine with stuff from a rattle can. Ive used two different brands before, VHT and Rustoleum. I like rustoleum better personally, it seems to have a satin finish to it and VHT appears to be more of a flat black color. Its pretty simple and straight forward to do though.
Take the housing off the truck, and clean really well. Then hit it with tint. You can lightly wet sand it, and apply some clear for a more finished look. I always mask off the white reverse light portion, i think it looks better.
Also, use light coats! The tint gets dark really quick if you dont pay attention to how much your spray
Sent from my 4G powered 5.7