Use the edge of a plastic opening tool to:

Pry the side button connector up off the logic board from underneath the wires.

Pry the speaker connector up off its socket on the logic board from beneath the speaker wires.

Carefully flip up the ZIF ribbon cable retaining flap on the socket near the headphone jack.

Be sure you are prying up on the retaining flap, not the socket itself.

Pull the headphone jack ribbon cable toward the left side of the iPad to disconnect it from its socket.