I bought it last year, so I doubt that that particular GB is still going, but you never know. PM rscheiring on R3V and see what he has to say.
To replace the headliner you have to remove:
- Rear Window
- Windshield
- Both rear side windows (coupe only), including the little wing behind them
- Sunroof panel, flip-up wind deflector, and some of the cable hardware
- Sunroof liner has to be taken out to be recovered
- Visor-area head panel, visors, check panel
- OMG handles, interior lights, upper part of door seals
- B-pillar covers, which means upper part of seat belts and those hooks as well
- Rear deck cover, which means rear seat also
- Rear seat side trim panels, under the windows
EDIT: Here's a picture of the disassembled stuff...


In the interests of full disclosure, I had to ask my wife to break out the sewing machine and modify the headliner as delivered - the loops/pockets that hold the rods ran the full width of the headliner on the new one, but the original has the pockets ending 4-5 inches back from the edge, to allow enough material to wrap around the C-pillar. So, the pockets had to be cut back then reinforced so they wouldn't tear through. Not a lot of work, but something to be aware of, particularly if you don't have access to a sewing machine.
In all honestly, given the amount of labor involved, unless you are absolutely committed to doing it yourself I would recommend you have a shop do the work. It wasn't technically challenging, but it was a PITA.
I used 3M Super Trim Adhesive, pn 08090, and followed the directions - 3 coats on both sides, let it sit for about 10 minutes, then stick it all together.