What I did was go to JoAnne Fabrics (I was like the only guy in the store :roflmao

and get one yard of the headliner material I wanted. Cost me $15. You'll need either fabric glue (better) or spray adhesive (faster, lazier, but more frustrating and not as good adhesive) to attach the new cloth. Fully disassemble the OHC, it mostly snaps together but can be a pain in the butt. Scrape/pull all the old fabric off, bring it into the shower and scrub the rest of the old decaying foam off, then glue the new fabric on. You'll want to stretch the fabric as you go - but follow their directions EXACTLY! I put my fabric on a little too soon after I sprayed it with adhesive and the foam got saturated with it and sunk slightly so it looks just a little lumpy, if I had waited longer it would not have done that. Once it's stretched on, wait for it all to dry (you might have to hold it onto the inside around the edges using tape temporarily) then trim around the holes and such. You'll want 1/2" to 1" of extra around the edges to fold back so it doesn't pop out. Reattach all the hardware and you're done!
The screw that holds it to the ceiling at the front is a 3" long #8 screw at least on a 96. The little plastic piece of trim in that recessed hole can be pried out carefully and the fabric removed from behind it. Then just find the hole behind the new fabric with your finger and jam the plastic trim back in (properly aligned, it has a ridge along the back edge) and it'll break the fabric and keep it under tension. I'm not sure how this all jives with the 97+ design changes but keep your eyes open while breaking the thing down and you'll be able to put it back together just fine.