Is there any possibility of fitting another engine loom, preferably from a manual car, which would remove the jumper wires you should have on the safety starter switch. When I fitted a manual to an auto Sunny there I modified the wires going to the neutral switch by putting jumper wires on a matching plug, or else the car wouldn't have started. Maybe the motor was earthing through the solenoid wire, which is what appears to have burnt out. Maybe Dapto wreckers has something, or any of the other wreckers near you. I don't know of any Sunny's here in Sydney, but maybe the wreckers at Cooma has something. I once had a 1200 loom burn out due to the cigarette lighter wire shorting out. I had to through the complete loom away due to the damage it did.