WTH is this thing called?!? and why are some of them black and some grey? Can they be removed and painted? is it difficult? I know these questions have probably been asked before but I can't search for something if I don't know what it's called. hmmm

 

I dont know what it is called, maybe the headlight housing would be my guess. But yes you can take off the clear cover to get to that piece and paint them. There are a couple of different ways, one is to put it in the oven for a little bit to loosen up the glue and another is to use a heat gun. I believe some people on here has done this and can point you to the right links for instructions.

 

here's a write-up on how to paint them.
doesn't seem too difficult.
i wanna paint mine sometime as well.

link