When my headliner went south (literally), this is what I did,
1) strip the interior seats and carpet (gives you and your poor unsuspecting friends who aren't aware whats to come more room to work). Also gives you a good reason and chance to REALLY give the seats and carpet a damn good clean.
2) remove the 'a' pillar garnishes, bolsters and c 3/4 garnishes.
3) remove the courtesy lamps and the rear view mirror
4) one person need to be in the rear of the car, one through the drivers door and one at the passenger door.
5) unclip the headliner and remove from the vehicle through the passenger door aperture keeping a close eye on the backboard and the making sure that it is supported through out.
6) place it face (headliner side) down on two saw horses, trestles or what ever you can beg steal or borrow
7) brush off the dust and loose detrius from the back of the head liner backing
9) build up 1 layer of medium weight Glass fibre mat on the back of the headliner backboard and leave to go hard
10) Carefully flip the whole assembly round so that the headlinerside is face up
11) remove the headliner and foam backing (assuming it han't already fallen off)
12 Again remove dust and detrius and apply GRP resin and leave to go tacky
13) build up 1 layer of light weight Glass fibre mat on the back of the headliner backboard and leave to go hard
14) Apply a liberal layer of PVA leave to go tacky and then replace the backing foam and leave to off (24 hours)
15) I got a piece of fabric that looked similar to the original headliner material and using the original, transfer the pattern to the new cloth.
16) using heavy duty carpet adhesive, spray one coat onto the backing foam and leave to go tacky
17) once tacky, lay the cloth over the headliner backing and starting from the centre, smooth it out so as there are no creases or wrinkles.
18) to quote Haynes, "refitting is the reverse of removal"
19) Go to the pub and buy your friends a pint
This may seem long winded and relatively labour intensive but It took me one weekend and cost a grand total of £65.00 including ale.
Hope this helps
