iFixit

Use the flat end of a spudger to disconnect the left fan connector from the logic board.

It is useful to twist the spudger axially from beneath the fan cable wires to release the connector.

The fan socket and the fan connector can be seen in the second and third pictures. Be careful not to break the plastic fan socket off the logic board as you use your spudger to lift the fan connector straight up and out of its socket. The layout of the logic board shown in the second picture may look slightly different than your machine but the fan socket is the same.

Lift the left fan out of the upper case.

Use the flat end of a spudger to lift the right fan connector out of its socket on the logic board.

It is useful to twist the spudger axially from beneath the fan cable wires to release the connector.

Remove the three 3.4 mm (3.1 mm) T6 Torx screws securing the right fan to the logic board.

Lift the right fan out of its opening in the logic board.

Pull the camera cable out of its socket on the logic board.

Don't lift upward on the camera cable as you disconnect it. Pulling upward on the cable may damage both the cable and the logic board. Pull the cable parallel to the face of the logic board.

Use the flat end of a spudger to pry the AirPort/Bluetooth connector up from its socket on the logic board.

Use the flat end of a spudger to lift the optical drive connector out of its socket on the logic board.

Disconnect the hard drive/IR sensor cable from its socket on the logic board by lifting up from beneath its connector.