Thanks lunatic. I've been using this diagram from the repair manual: https://www.dropbox.com/s/2pi4196d0k...ng-diagram.pdf

From what I understand, 12v positive lead is the red wire (via the battery fuse). When key switch is on, power feeds to both red/grey and red/black wires. Am I safe to think hot wiring those wires will bypass the keyswitch entirely? Red/Grey leads to headlight (via the Aux fuse). It would rule out the key switch being faulty.