Speaker Size is 6 3/4 to be exact. 6 1/2 will fit as well, you may need ring adapter, though.
As for the door panels, got a wife? Mom? older sister who cooks? Great, then go inside get their spatula, and pry the door panels off, starting from bottom, make your way up, careful not to scratch anything. Once you pop 2-3 of them (there are 10 in front, 9 in the back) get the spatula out and yank the door in straight-out motion.
You may end up breaking or leaving one-two in there, no biggie, if more damage, you can get a set of clips from auto store or home depot.
see my pix here:
http://gallery.jeepprojects.com/categories.php?cat_id=12&sessionid=be5f19873fa87c09a21b6ab9170e13e0
If you look really closely, you will see my special prying tool in this shot..
You must be registered for see images
Spot it yet?