How do I get these parklights apart?

[superdav]

I started polishing parts to store so they'll be ready to go on when I put the truck back together, I put the lens on the buffing wheel to see how it would look and it looks brand new on the outside but dirty on the inside and the silver is coming off so it needs paint
I can't tell if it's glued or maybe even heated and pressed together.
Anybody take one of these apart?