Hi
Let me start by saying that if you try to repair or open your XP, it is on your own responsibility! If you still have warranty, you loose it by opening the XP..
When that is said, the XP is fairly easy to open. Place the XP upside down; be careful with the bend/modulation stick! Remove the screws in the bottom of the XP, and remove the bottom plate. Remember to unplug the power before opening!!
The disk drive is now clearly visible (if my memory is correct). The disk drive appears to be of the standard IDE type used in your PC.. To be on the safe side, I would order an original Roland disk-drive. Loosen the diskdrive and the cables, and substitute it with a new one!
I have NOT done this myself, but I have opened the XP-60 once, and both changing the internal battery and the disk-drive appear to be quite easy.. The XP is internally very well constructed, and has very easy access to most components..
But be careful anyway; having somone assisting you is not a bad idea. Maybe you know someone with experience from repairing electric/electronic devices..
Hope this was helpful to you..
Stig