well, the pertronix did fire the coil (did it?) so it did drag off the negative side. If you have no spark to plugs, its losing the bridge between the coil and the plug wires...the rotor. I once had a rotor that was internally grounded sitting on the shaft. Check continuity between the center tower and ground while distributor is in place, then check continuity from tower to carbon button in cap and finally the rotor tip to finger. A grounded spark path will not create a spark. My test would be to watch the coil lead sitting close to ground while cranking. If it sparks, your close.
