There are tools on the market from Team Xecuter specifically designed to do the job, but why go to that expense? The easy, fool-proof method which I use works perfectly for me with no hassle:
1. Take the top and bottom plastic sides off.
2. Take the faceplate & Warrenty Sticker off.
3. Lift up the 4 plastic tabs on the front.
4. Turn the console so it's front is on your desk (Back is in the air, tabs facing you). Pull the 2 shells apart as far as you can.
5. Use a precision screwdriver bit (smallest) and push it through the holes. The tabs 'click' and the two halves of the shell come straight apart with no fuss or problems.
Works for me anyway