If you follow [guide|25228|this guide], you can take off the back panel. From here its relatively easy to access all of the buttons.
[image|859453]
You can remove the connection and screw (indicated by red on the above photo) to take out the 8-way controller. The plastic control dpad itself is simply clipped on to the electronics and can be removed by gently pulling back the clips (I used a very small flathead screwdriver).
[image|859454]
As you can see underneath was quite dirty, and cleaning it has helped somewhat but not completely. I will need to source a new 8-way controller despite the cleaning! :(