I believe the Press Fit connector only fits on V2.4 (there are 4 versions) boards, and since you have an older board, I wouldn’t use it. You may need to cut the connector off and just solder the wires directly onto the board (PWM and GND) at the location outlined in the JTech Photo.
Having said that, I recommend that you contact JTech for detail instructions for the older V2.1 Board.