I love bench racing and keeping it friendly here goes....with points closed and one lead of the voltmeter at ground potential and the other on the feed side of the resistor you will read 12 volts not 6. If you move the voltmeter lead to the other side of the resistor you will read about 8 volts assuming you have a 1.5 ohm or so ballast resistor. If the resistor is bad(open) you will read "0". That is the important point..."0" volts on the downstream side of the ballast resistor means failure.
The ballast resistor is in series with the primary side of the coil to reduce the voltage (current) to it in the run position.
I think I have it right but never know. I have let the smoke out of many wires before!
Maybe Hotrod Lincoln will jump in here and correct me.
