I have a 6300, and I took it apart about a year ago. To get the top off, you have to:
(1) take off the front panel. To do this, you need a small screw driver to pry open the clips that hold it on. They're just above the speaker on the lower front, and off to the sides.
(2) remove the side panels. Tap them forward and they should come off.
(3) remove the top plastic panel. I think it slides backward; you'll have to experiment here.
With the plastic top off, you should then be able to get the metal top off. I'm not sure exactly how this is done, but I don't recall that it was too difficult. Good luck!