Prepare work surface by placing a clean and dry towel down on a desktop surface.

Place the computer face down on the towel so that the bottom of the unit is facing you.

Loosen the two phillips head screws in the bottom left and right hand corners of the computer, as highlited by the yellow circles in the image.

Note that the screws will not come out, but as you loosen them, it will force the separation of the corners of the rear cover from the computer.

Once the screws are loosened completely, use plastic spudgers to completely separate the rear cover from the rest of the computer.

Use multiple spudgers to help with prying the pieces apart. Particular sticking points seem to be in the center at the top and bottom of the chassis.