Use a firm plastic edge to scrape the thermal material off the processor.

When replacing the logic board, make sure all cables are routed around and above - not under - it, and to connect the two cables that do go beneath before pushing the board into place.

Place the logic board back in the computer, trying not to move it around once the processor has come into contact with the newly-applied thermal paste.

Remove the two small black Phillips screws from the left ambient light sensor board.

Lift the left ambient light sensor board out of the computer, removing tape as necessary.

Deroute the Bluetooth and RJ-11 cables from around the left side of the speaker.