Pivot the keyboard further up until you can see the connectors on the underside of the keyboard

Detach the connectors that connect to the trackpad.

Most of the time, these connectors will have a lip or a tab along the top that can be used to push the connector out of its socket.

To disconnect, use the wide end of a spudger to push on the connector tab to slide it out of its socket.

It may take a lot of force to disconnect the cable. Go slowly, and don't pull on the cables.