iFixit

Turn the computer over and open it up.

Remove the following 14 screws:

• Six 2.5 mm Phillips on either side of the keyboard area.
• Five 4.5 mm Phillips on the left half of the keyboard area.
• One 7 mm hex in the upper left corner of the upper case (a T6 Torx driver will do the job nicely).
• One 15 mm Phillips in the upper middle of the keyboard area.
• One 16.5 mm hex in the upper right of the upper case (again, a T6 Torx driver will work well).

Peel up the two pieces of foil tape on the left side of the keyboard area.

The connectors at the ends of the cables are attached very firmly to the sockets on the logic board. Pulling directly on the cable will either separate the cable from its connector or the socket from the logic board.

Carefully disconnect the microphone and power cables from the logic board. Using your fingernails or a dental pick, carefully pry the connectors from their sockets. Make sure you're pulling only on the connector and not on the socket.