Step 22
The first frame shows a tab in the "locked" position and the second frame shows the same tab in the "unlocked" position.
Use needlenose pliers or a spudger to bend each of the four tabs so that they are all in the "unlocked" position.
Step 23
Slide the keyboard ribbon out of its connector.
If the keyboard ribbon won't slide out, make sure that the black plastic flap holding the ribbon in place is vertical.
Step 24
Place the upper casing on its edge and use a spudger to push the keyboard away from the casing, poking the spudger through the central keyboard screw hole. Grasp the keyboard as it separates from the casing.