Hello Endo
Power to the start/kill switch is as follows
Power is via a red wire from the rectifier to the ignition switch.
When ignition switch is on power to the start/kill switch via a white wire. via the 4 way connector (these used to be 3 way but later models have a black earth wire as well in the 4th way)
From the handle bar switch the other white wire runs to the coils via the 3 (4) way connector.
The black/white wire in the connector block is from the start button to the starter motor relay.
The ignition switch has 4 wires, red is live feed from the rectifier, white is described above, brown runs to fuses F1, F2 and F3 in the fuse box and powers almost everything except the parking lights, these are fed from the ignition switch to fuse F4 via the green wire.
I hope this helps. If you would like I can send you a colour wiring diagram for your bike for a small charge! click here for details
Best wishes Chris