Today, I worked out the starter contactor changes. The harness was constructed to utilize all of the bus manager functions relating to single and dual battery starts. The Z-14 can do the same thing using the crosstie. I could have simplified things by just using the bus manager.
Because of those decisions, it was necessary to remove a couple of unused wires from the harness. This was easily accomplished. The next task was to determine the new wiring design. The main issue is that with the current wiring, with the VPX handling the start function, the start button would be active any time the main power was on. The keyed switch for the bus manager would keep the ECUs, ignition, and fuel pumps inactive until switched on but the start button would always be active. For safety reasons, I decided to replace the single pole key switch with a double pole key switch. This allowed me to use the second pole of the switch to control the start button through a relay. The end result is that all engine systems are inactive UNTIL the key switch is turned on.
Standard techniques were used to install the new key switch and connector. The new swith is made by the same company as the old one, so it was a direct replacement.
Next, I routed and connected a #20 wire to provide essential bus power to the fuel pump mode switch.
The mating connector for the key switch was then installed utilizing the harness wiring plus two additional wires.
