Step 7
Remove the two Phillips screws on either side of the battery contacts.
Step 8
Breathe deeply. Trying times are ahead, but we promise the lower case does come off.
Push the thin rims of the lower case surrounding the battery compartment in, bending them past the tabs, and then lift up to free that corner of the lower case.
Step 9
There is a slot on the wall of the battery compartment that locks the lower case in place. Use a small flathead screwdriver to pry out the slot's lower rim and pull up on the lower case to free the slot from the tabs holding it.