The old headliner, very dirty, and sagging very badly.
First, start by removing the rear seats, both the backs and the bottom. Sorry for the poor pictures, flash acted up.
Remove the passenger rear lower plastic panel. This is held in place with just stiff plastic clips.
Pop off the plast cover from the passenger seatbelt and unbolt the assembly-14mm.
Now remove the passenger rear upper plastic panel. There are two plastic screws holding it in on the bottom, and the rest is just plastic clips. You will have to fiddle with the rear deck to wiggle out the back tail of this piece.
Next remove the passenger front upper plastic piece. This is just held in place with stiff plastic clips.
Remove the driver side front upper plastic piece. This is just held in place with stiff plastic clips.
Now removing the remaining interior pieces including the dome light, sun visors, rear view mirror, handles and hangers.
Remove the rear upper plastic trim that hugs the rear glass. This is just held in place with stiff clips.
If you have a sun roof remove the sunroof liner that wraps around the opening.
To remove the liner, lay both front seats all the way flat and carefully lift the headliner and remove it out the passenger side door. Here's the old one, all shabby.
Bare metal roof.
Remove the old fabric and old foam. In my case, the original cardboard was so damaged I pulled one from a junkyard. Make sure it's clean. Layout any old tarp or painters drape on the ground. Now layout your new material(use foam prebacked fabric) and size it up over the headliner board and cut it from the roll. Fold up one half of the headliner back on itself(i layed down clean junk tshirts between the layers of fabric in this step).Using your interior spray adhesive foam spray both the exposed cardboard and the backside of the fabric. Wait 2 minutes for the glue to tack up, the have an assistance help you slowly lay the fabric back down. Use only the heel of your hands or side of your fingers to smooth down the fabric. If you use youre fingertips you push in 'dents' that may or may not release later on. Then slide the tshirts ontop of the fabric you just glued and fold up the other half. The tshirts keep you from overspraying onto the top side of the fabric.
Here's the fabric glued down
Let the fabric rest for a couple of hours then pick it up, and lay the same tshirts down on the floor on the opposite side, then lay the headliner face down so you are looking at the back. Spray the glue all along the edge of the cardboard and exposed back of the fabric. As before wait 2 minutes then start wrapping the material over the back, making sure not to make any creases or folds. Wait a few minutes then use a sharp razor blade to slice off the extra fabric more than an inch.
Now we cut the holes for the little bits. Spray a little bit of glue across the hole making sure to get the back of the fabric and the cardboard, then slice an X in the fabric with the razor blade and pull up the pieces, glueing them to the back of the headliner. I did this for most holes but not all.
I sliced a similar X into the sunroof section, then brought the headliner back out to the car. Install the headliner in exactly the reverse procedure as above. The last step for mine was to stretch up the headliner fabric and secure it in the sunroof opening using the liner and trimming the excess.
Here is the finished product. I went with a foam prebacked grey suede that was very similar to the original headliner fabric color. Next up I need to wrap the sun visors.
congrats you have successfully recovered your headliner. You can now ride around without it looking dirty or sagging.