How do I remove the plastic cover of a headlight to paint the inside?

I mainly want to remove the oxidation from the inside. I already buffed out the front but i need to clean dirt and condensation from the inside and possibly paint the chrome black. I know you can do this on titans and newer tacomas but can you do this on every vehicle?How do I remove the plastic cover of a headlight to paint the inside?
Some head light lenses are clipped on and are silicon-ed sealed at the same time.


They can be removed and new clear silicon has to fitted,it is sold by tubes.How do I remove the plastic cover of a headlight to paint the inside?
You just need a lot of time to waste most probably a heat gun and a good knife like an exacto and cut away at the silicone or whatever is holding it together and then put it back together, I would suggest black urethane to close it back the type they use to put on windshields I know 3M has a good one.
any that are black seal together can be done. takes a heat gun and some time