Thanks guys.
I've been looking around online and I found a guy on the Stovebolt website who said he'd made his own headliner using ABS sheet. I did a search and came up with this source:
http://www.usplastic.com/catalog/ite...3013&catid=715
It says it's heat form-able so I am wondering if I can just cut it to approximate size and use my heat gun to gently form the corners. I guess I don't care if I heat it enough to lose the texture because I can always use spray adhesive to face it with Naugahyde. I think my fall back position will be fiberglass but having little experience with it, I think it would be a real challenge for me.
Let me know if any of you have experience with heat-working sheet ABS. I know NOTHING about ABS other than ABS drain pipe!
The thought did occur to me that if this works I might be able to use ABS pipe glue and a thicker sheet stock to make an overhead console. I'm not sure I LIKE an overhead console but I'd like having the option. Your thoughts?