[midgetracer]

Bob,
The tests indicate that your diode is working. Think of a diode as a one way valve. It lets current from the generator to the battery, but does not allow the battery to send current to the generator and make it try to be a motor. Since the Model A is positive ground, if you put the black lead of the ohm meter on the generator side of the cutout and the red lead on the battery side and you get continuity, the current from the generator will reach the battery. If you switch the leads and you get no continuity, it indicates that no battery current will reach the generator. Eureka.. The cutout is doing its job. Since you get sparks from the generator post when the engine is running, It indicates that the generator is putting out voltage. Remember, the diode will not let battery voltage flow backward to the generator, so the sparks are not due to the battery.