sorry for the vague DIY, but i think this should be enough to get you going.
this will work with your blacklines only. your oem can not do this. you can use your oem as practice.
before doing this, please becareful with the hot boiling water...do this at your own risk.
1. remove all the electrical part. now we are left with just plastic
2. fill a big pot with water. put it on the burner.
3. once it starts to boil drop your taillight in
4. let it sit for 15 minutes or so.
5. take them out and try to find a location to pry them apart. (once you get a little opening, the rest should follow. BE VERY CAREFUL YOU DO NOT CRACK THE LENS)
6. remove the clear pieces underneath.
7. cover up all the area you do not want to be painted.
8. paint the housing with the color of your choice. ( for whitelines, do not use white paint. use chrome paint).
9. use a dremel to clean up all the black plastic that was left on the lens when you remove the lens. (you will know waht i am talking about when you do this).
10. make sure paint is dry.
11. seal that sucker up and you got yourself ____lines.
12. i havent got this far yet. but i was thinking of using silicon.
here are some pictures.