I used Plasi dip to coat them. It’s a very easy process. I painted them on the truck by masking off everything around them. Some others that have done the same thing have reported theirs have bubbled after driving them for a bit. I have had zero issues with mine. Since painting them I have been on a couple of long trips where I was driving for several hours and have several thousand miles on the truck since painting them. I did clean mine well with alcohol really well before painting them. The Plasi dip is cheap and can be peeled off if there is an issue. It’s worked really well for me.