And what the hell do I do about my sagging headliner?

Here's what I did. I went to the local fabric store, they now sell headliner material. I them went to my full line auto parts store and got a spray can of SEM Products fabric paint. This I used to get a better color.
Then I pulled all of the mouldings, that car didn't have a sun roof. I pulled all of the fabric off and scrubbed the roof inner panel with everything I could find. Adhesive remover, lacquer thinner, everything. It helps to use some kind of scrubber, I used a plastic, open grain, pot scrubber.
When it was clean, I went back to the auto parts dtore for a couple of cans of spray adhesive. Start at the centerline, front to back. Then pull at the sides. Don't try to glue the whole thing at once. Came out very nice.
Don't try to pull the inner liner, it is glued to the metal. On the other hand, if you are ever doing a SAAB, the liner comes right out and makes it a lot easier.

where you have a little vent. You know, that little guy that pops up. The liner keeps falling off it and I tried glueing it but the metal wont let anything stick to it. It's almost like a molded soft plastic with fabric on it.

Thanks, I will give it a try!!