There is a large rubber grommet separating the keyboard from the motherboard. Its job is to help shield the motherboard in case a liquid is spilled into the keyboard.

The top edge of the grommet has a notch. Insert a fingertip or screwdriver and carefully pull the grommet loose. It is held in place by a weak adhesive.

Slide the grommet along the keyboard ribbon cable, towards the keyboard, and out of the way of the ribbon cable sockets.

NOTE: the thin grommet tears easily! This damage can reduce your laptop's ability to withstand a liquid spil.