I could not get my big fingers in to grip the wires. I used a small flat bladed screwdriver against the tiny ridge on the top of the connector. I pried against the board.

I used 2 screw drivers as suggested, and pulled towards me with my palms against the sides of the case. Even with a lot of muscle, I failed. The solution was to get a helper on the opposite side of the table. Using the fingers of both hands along the circular opening in the case, the helper pulled as I pulled on the screwdrivers. They should be kept vertical, so as to not damage the board. There is no way the procedure pictured in step 23 would have worked for me. My board must have needed at least 20 pounds of force to move