Using the highly informative maintenance guide on here, I renewed the headliner in my 97 estate today. I'd bought some head-lining cloth at the NEC last November, so with plenty of spare time at the moment, I decided to give it a go. The old one was out in an hour, I carefully peeled off the old cloth, wire-brushed the board, spray-adhesived the new cloth and the board, and got my brother to help put the two together. After trimming off the excess it was ready to refit. It came out great.
One thing I'd add to the guide is that the cargo-net roof fitting holes are held in by colour-matched spreader pins - if you get your finger inside the hole you can partially push them out from the inside and then pull them out by grabbing them with small wire cutters/pliers, making removal 10 times easier than forcing them out like I did with the first one. The whole job took about three hours, with the well advised cuppa breaks.