You have to take the door panel off.
Behind the door handle are 2 little plastic buttons pop those out and there are 2 T25 or T30 torques screws, I don't remember the size off the top of my head, remove those then carefully pry the door panel away from the door, you will probably break a few of the clips, just buy a package of new ones, they are like $2 from the parts store.
As far as speakers, try a set of Alpines, I had a set in my 97 and they sounded pretty good.