Remove all screws from the logic board cover. Two are recessed in the middle; others are along the edge. More will become visible as other parts are removed. It's like a game! You can start with the screws holding in the black plastic pieces, but I started with the most visible and went from there.
There are two wires (shown in the third picture) coming from the logic board and connected to the Wi-Fi antennas. These are delicate. Do not break them.