I don't know of any sites, sorry. I own a '95 GA and have replaced the rear speakes more than once. What I had to do was remove the trim starting at the pilar between the doors. (Four door) Two door would probably be just behind the doors. Both top and bottom because of the way it was all put together. Be especially carefull with curved pieced back by the window, and the pieces that cover the pilars of the back window. Then the seat should lift up first, and out second, on each side. Then finally the cover should come off.
Couple of notes. I have a four door as I stated before. I'm not sure how much easier or difficult a two door would be. I've seen inside one. Another note, a friend of mine has a '94, and we noticed a key difference. Her interior light which she has two of are located towards the outside on the side between the doors. Where mine is in the classic center position. I'm not sure if this may effect what you are trying to do. That's all I know about it.
Good luck
Tony