OK, for the autopilot only: Locate the green 12-pin Deutsch connector labeled P-5 that is on the main controller harness. Remove the plugs from cavity 2 and 7 and connect wires to two Deutsch pins, and then insert these into cavity 2 and 7. Connect the other ends of these wires to the N.O. terminals on the foot switch. Polarity doesn't matter here, they just need to be hooked up so closing the foot switch temporirily shorts them together. I did not connect pin 11 for my install and it works very well. While you are here, you can also connect a wire to the same two pins and run it to a handy place for a push button switch that you may wish to use for a hand engage. That switch should also be a normal open that closes only as long as you push the button. In the pic, notice the white wires coming from the Deutsch connector. One runs to the foot switch and the other goes to a push button switch on the console.

For the EZ-Steer, I used a DB-25 male to male serial cable, as I was attracted to the nice molded and sealed ends on the cable. Cut one of the ends off and use the wire that leads to pin 10 (white on my cable) and pin 11 (pink) to go to the foot switch. Again, polarity is not important here. Hook one to one side of the switch and the other to the other side. While here, you may want to wire in a buzzer that alerts you to certain events with the system. I used a SC616NR Mallory Sonalert. Use the pin 7 (blue) as the + and pin 20 (red/black) as the - to run to the buzzer. These wires need to be hooked to the appropriate terminal on the buzzer (+ to + and - to -). I really like the Clipper Linemaster 632S footswitch. It is heavy enough to stay where you place it and very rugged. I believe that colors will be the same on all serial cables, but you should check to make sure that the wires you are using are indeed connected to the desired pins in the connector.