The relay idea might work if you have the ECU connected to run and then use the relay to also connect to 12v during start. I haven't tried that method but it seems like it might be worth a try. I'm not a big fan though since now you've added another relay to the clutter of the ballast resistor and the confusion of having a J1 and a J2. Why have all of that complexity? The Sniper just needs 12 volts so why make it so complicated.

On my car I just eliminated all of the Mopar ignition monkey motion. I never like the ballast resistor idea anyway or the Mopar ignition box. I also got rid of the voltage regulator and used an internally regulated alternator. The Mopar engineers in the 60's and 70's had a lot of little boxes and things on the firewall and inner fenders. I never like that look. The modern approach is to use the ECU to control all of that stuff and get rid of the analog parts.