is it the actual cd-rom drives or just the housing/framing stuff that you can't get out? you may have to take off the other back panel to get to some screws if it's the actual drives. and to get the frame out, if they're riveted to the actual frame of the tower, just take a flat headed screwdriver and give em a whack with a hammer. they should pop off really easy, they're cheap. just be careful not to smash it too hard, the frame metal is usually pretty cheap too and will bend easily