5. Repeat the same ID process for each of the remaining 9 pins of the 10-pin interface. Connect wire 3 of the 2x5 pin IDC ribbon cable to ground. Also, wires 4, 6, 8, and 10 are all connected to pin 6 of the Mark II 6-pin interface. These are ground (GND) connections. I used a black extension wire to bundle all of the GND wires together prior to soldering just the extension wire to the Mark II GND pin 6.