Ok that's why I got the backup plan orange Mopar ECU so just tape hide the unused coil/balast/ECU for later and in the loom. The yellow blue wire Im guessing is the one you tapped into, looking at your photos here.
If I recall correctly I had a brown going into the ballast and a blue coming out. Regardless.. whichever gives the 12v ignition on (after bypassing the ballast) is the one I used.