Find the key on 12 volt connector on your windshield wiper motor. Then when you get a wire cut to the right length, crimp a male blade connector on and shove it in the hole you found that has the 12 volts - key on. This is the first time I've heard of fusing that connection, never had a problem with my set up on two trucks.
The problem comes when the coil element goes out. You have been fortunate if you have not burned out an electric choke yet.
Definitely fuse the connection.
Trace the wires from your voltage regulator to your alternator. One wire will run exclusively between the VR and the alt. The other runs between the VR, alt, ignition switch, and ecu. This is the wire you want to hook you electric choke up to (ignition switched 12 volts). Not sure on a '78, but IIRC the wire you want will be either red or blue.
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