How to remove ambers reflecters in headlights on 03-04 SILVERADOS

Hello

I was told that you can just heat up the lights and pull them apart and the refrlecters pop out. Is this true? And how or what do you use to reseal the lights so no vapor gets inside them? Is it just black under the ambers? If what i'm saying is incorrect please correct me. I appreciate all replys, tips, and info.

Thanks