Just installed the headliner in my Cuda, seems daunting and confusing but is actually pretty straight forward. I do have hushmat stuck to the roof and a not too worried about it as the car will spend most of its life inside but that said that stuff is REALLY sticky and I don't think it is going to fall off anytime soon.
Some tips for anyone thinking of doing this; first buy/obtain about 4 boxes of mini binder clips from your local office supply store (or work...). Follow the online instructions to get the headliner into place, then use the binder clips liberally to begin to stretch it out. You have to work initially back to front, then side to side. You kind of work side to side and back to front simultaneously and this is where the binder clips really work, they allow you to stretch and reposition.