'68 barracuda ignition switch power on issue

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The MSD's on/off wire can be connected to either Ign 1 run (wire J2) or Ign 2 start (wire J3) as long as they ballast resistor is there. If the ballast isn't there, then the two wires need to be joined directly together. If someone has removed the J3 (16 gage brown wire) from the engine bay, then the car won't start.

MSD 6 wiring: 67 Cuda Autostarting