At this point in time I'd disconnect ALL wires in the offending circuit and w some jumper wires w alligator clips on each end I'd KISS and run a jumper from the battery positive post to a ballast then from the downstream side of the ballast w a jumper to the positive primary coil terminal and from the battery positive post to the "point of the ECU that way the coil/ecu/ballast are being fed directly and as said check the dist pickup polarity (just switch it once and retry it w no other changes to confirm/eliminate that circuit) Sub in another known good coil & retry (w the jumpers) then try another ECU (not an orange one). Either one of the components is bad or the supporting wiring is and any of the electrical component can act up when hot and ohm out/act good when cold. We'll get it