"Someday, I'll wire in the oil pressure cutoff switch that kills the fuel pump when the engine oil pressure drops below 7psi - even though the ignition switch is in the RUN or START position. For starting with such an arrangement, you can rely on the fuel contained within the carburetor bowl - or wire an override momentary switch that you push and hold while cranking until you get oil pressure showing."

Since the carby motor has one coil b+ wire hot at start, and the other one hot at run, a oil pressure switch could be wired to the one hot in run with a diode, and the pump could be wired around the oil pressure switch with another diode and the wire hot in start.