Has anybody removed slapped felt headliner right against the roof?

**DANGIT...noticed the title is off. That's what I get for posting from my phone***

I'm trying to think of ideas to keep the car comfortable, but I also want to leave room for the cage. The bowed headliner in my 70 swinger is needing some love in the future, and rather than reupholster the existing style, I was wondering if anybody has had success tossing some padding and then vinyl or felt directly onto the roof of the car. I could do the cardboard backing route, but even those hang down a bit, not to mention they're super brittle if I was to use an existing headliner for the template or even as something that I'd reupholster.

Ideas? I'd have to figure something out with the channel that runs across the center of the roof, but don't think that'd be too much of an obstacle. Might anybody have or know where I can find some shots of the interior side of the rear quarters?