After removing the screw, pull up on the motherboard to release it from the circuit board (green tab, see Figure 11). This will simply snap out, and does not require too much force.
Use the light blue wedge tool to remove the back. The circuit board will slide out of the slot and will stay attached to the remaining front half of the phone.
Secure the motherboard by screwing the small black Phillips head screw into place, located below the right speaker. Note: You may need to remove the right speaker in order to replace this screw.