The ballast resistor was added during 87. My family's first Jeep was an 87 XJ, and it had one.
But that's beside the point. The resistor is bypassed during startup. If the resistor was bad, it would start, run for a second, then die. My first personal XJ did that when the resistor went out.
If you have one, it will be located on your driver's side inner fender. To jump it, simply pop both wires off and connect them directly.