I couldn't find an electrical drawing to make sense of the bundles of wires under the dash - I had an issue with a loss of power to all of my dash breakers which I resolved. Tracing out wires, I noticed that the dash also powered the ignition switches. A red/purple wire from the engine ran to a 10 amp breaker and then to the ignition switch. From the switch was a yellow/red for the start and a purple for the accessories - just like the service manual showed. This is were I got confused, the dash also fed power to the ignition switch. With the engine battery turned off, I could start the starter solenoid (with the normal dead battery sound). I disconnected the dash fed wire to the ignition switch, now the engine battery needs to be on for it to start in a normal fashion. Both engine were done that way. All I can think of it is for emergency starting, when the battery voltage drops, giving full battery power to the ignition circuit (spark). Has any one ever seen this?