I guess one could consider an ignition circuit as 3 resistors in series. The first one being from battery + to coil+, including fuses, wiring, switches and connectors. The total resistance should be very low, approaching zero ohm.Perhaps we skipped a step between now and mid-July (and started checking voltage); did we ever verify that points were opening and closing continuity to ground (esp. RH) and verify timing?
Next resistor is coil+ to coil-. Should be around 4 ohm on a stock points coil.
Last resistor would be coil- to ground (battery -), including connectors, points and ground connection between engine and frame/ battery -. This should also be as low as possible, when points are closed. If using the ohm setting to check this, disconnect the capacitor (condenser) !