Step 25
Remove the following 5 screws/standoffs:
Four black T6 Torx screws securing the left I/O board to the lower case.
One 4 mm standoff located between the audio jacks.
Step 26
Lift up the right side of the left I/O board and slide it out of the computer.
Step 27
Remove the three silver Phillips screws securing the ExpressCard cage to the left I/O board.