Painting Parktronic sensor

I've been very lazy about one particular thing on my car. Fairly soon after I bought it I had a Parktronic sensor replaced under CPO but for some reason it wasn't painted by the dealership and I couldn't be bothered to take it back in and the next time the car was in was much later. Been a few years now (yes, years! the shame!) and yes, I'm thinking I want to paint it now!
Am trying to think of the best way to achieve this without compromising the Parktronic sensor's fucntionality. Do the Parktronic sensors have special paint? Just one coat? I've never actually painted anything on a car before, not had anything that needs doing so treat me like a fool on this

Thanks!
When you get them from the dealer, they come in this whizbang box with a proper size cutout.
I sprayed them with a single layer from a rattle can. I got phantom readings. Could be that the sensors were bad outta the box. nevertheless I now run them without paint.
Easy way, just just a very thin coat from a touch up paint bottle.
Thanks!





