After removing the screws in the front, if you can't remove the drivers because the seal is too tight, lay the speaker face down on the floor with a couple seat cushions under the speaker, not the driver you want to remove. Let gravity do the job overnight. I've had to do this a few times in the past. Be sure you're on carpet so the driver doesn't hit a hard surface. If this doesn't work, try using a larger threaded screw and screw by hand into the hole the screw came out of. After a couple turns, use a pair of pliers and pull on the head of the screw. If it gives a little, do the same thing at more screw holes until the driver comes out.