power source for choke

Add a relay, and a couple of fuses.

Pull the power for the relay from the start solenoid, through a 30 amp fuse. Put all of the loads on that relay, with fuses as needed. Voltage regulator, choke, ignition, etc.

Switch the relay coil on with the old ignition circuit. This way none of the loads go through a 40 year old ignition switch, and the voltage regulator, ignition & choke all get a full 12v.

B.