I need tips on how to semi black out or paint see through taillights

[turbotim23]

Hi I'm looking to semi black out my taillights but just part of the taillight. There's a 1in. strip on the top of the taillight I want to stay red as there is going to be a red 1 in. stripe on the sides of car and I want it to look like the stripe curves around the rear of the car. Anyway I would think you'd have to use special plastic cleaners and clear plastic sealer on the lens but what about paint ? Will any black paint work if it's thin enough or is it better if it's b/c? completely different from this, have any of you tried filling in side marker lights with bondo then wet sanding to the point it's soo thin you can't tell the light is there but the light shows through the bondo and paint when lit. I've seen this done on show cars, it looks great but am not sure how long it lasts with out cracking the bondo and looking bad. If you can give me any tips on how to do any of these things. Thanks

 

[TAZ]

The way I normally smoke out lights is to make sure the lens is perfectly clean. Take a gray scotch brite to it. Add a coat of adhesion promoter. Then spray a true clearcoat with hardener mixed with black. I normally mix in about 10% black. Then finish with straight clear/hardener (no black)
In you case, you can mask off where you want to leave the red. Then do the black/clear. Remove the tape. Then straight clear.

As far as the second question, you can do this. I have had problems with seeing the edge of the light though.
Motorcycle rear fenders and bags normally do this process so only portions of an LED light show through.