can/has it been done?? home made headliner...

I put a fair amount of thought into that subject before I painted the heck out of my cardboard liner with flat black using a roller.
I was thinking that house siding insulation foam boards, contact cement and my heat gun.
Then cover the foam with that thin netting backed foam rubber material they use for upholstery once the foam was up, and material over that.
The foam rubber reinforced with netting should hide the seams in the foam.

A good insulation between me and the metal was also a priority living in AZ.