I've done a few headliners. It's actually pretty easy. I had plans to do a desert digital camo in my car, but decided not to since I want something new. I still have the fabric though. Make sure you get the fabric with the foam backing. I searched for mine on google and the website had a lot if different patterns. Jo-anne fabric sells black and grey I think.
Tear off the old one and use a wire brush to get all of the foam off. Don't go into the board to far.
Lay out new headliner fabric and cut to size with a 1/2 inch over hang. Don't cut out any holes just yet.
Spray adhesive to both the fabric and the backing in sections. Don't do it all at once or it can start drying when you are trying to stretch it out.
Once you get the fabric tight and straight, wrap the over hang around the edges using the same gluing method.
Let that settle for a few hours then from the top, of the backing opposite the headliner, cut out your mounting holes, dome light, and speakers if you have them with a small over hang to wrap the edges.
Glue those back the same way and reinstall.
Takes a few hours and your arm get tired from brushing but you will save a lot of money and have the pride of doing it your self.
One more note, don't use too much glue, just enough to get a medium covering, other wise it will soak through, depending on the color it will be a little darker.
Did that on my first one I did.
O|||||O 1981 CJ7, 258, 4 speed..If it ain't cut, it ain't custom.