MSD 6al issues - bypass ballast resistor

Sorry I cannot tell from your photo. The best thing I can say is look at the MSD diagram. The MSD violet is going to the bottom wire in the photo, what I'm calling the distributor male, not the male on the old ECU end of the connector

If it runs poorly that may be the issue

What this does is to offset the timing (spark) in relation to when the rotor in the cap reaches the wire tower contact