Trying to start a 340 4speed Challenger. While starting you have to hold the ingnition all the way over while someone jumps the relay switch. When you let go of the key it dies. Any ideas? Ignition switch?

Your having to jump from the large "batt" stud on the starter relay to the brown solenoid wire next to it 4 it to crank plus hold the key to start? Recently (re)wired or all of a sudden? Might start w checking the bulkhead w these circuits & see w key held to start if you have fire (A) to the yellow solenoid (start) wire that goes to the relay for the cranking prob and (B) see if you have fire to the brown wire (ign2) ballast bypass while starting circuit out to the upstream side of the ballast. 2 or 4 terminal (dual) ballast?