Possible MSD 6AL failure

Been a while, thought it'd be useful for others to have an update.

1) Bought a spark tester. Tested the spark and all seemed to be working as normal. I couldn't get it into failure mode so I was never able to test the spark in the right 'scenario'.

2) My Blaster 2 coil was mounted horizontally and MSD requires that it be vertical. On another thread, many owners indicated they've run them horizontally for years w/ no issues. I was open to swapping it out to see if the cooling might help. I swapped for a Blaster SS with a plate adapter for my 360LA. Fired up fine and worked. Then the problem came back at least once. Swing and a miss.

3) Now I know that my MSD tends to run REALLY hot. I've read that the digital ones (Model 6425) may run cooler since it's all digital. I don't know how old the 6420 was but I was open to giving this a shot too. I bought a new 6425 and in preparation for it's arrival, I started the tear down of the wiring of the 6420. That way the swap out would be quick. As I was dismantling the wiring, I noticed that the my mechanic didn't wire my kill switch as I had directed him. But because I couldn't see what he had done, I only assumed he did it right. He was supposed to (per my directions) pull the white wire to the switch because I'm running a magnetic pickup. That meant that every time I turned on the kill switch, I was grounding the + terminal on the dizzy. Ugh. 67Dart273 wins the prize for the correct suggestion.

I debated whether to just return the 6425 and keep the 6420 in. But I liked the idea of having it wired once and if it fails, I can just swap the box w/o rewiring. With the 6425, Blaster SS, and CORRECT kill switch wiring, I haven't had a single issue. It's actually firing up faster now as well.

This last piece of data is just that, data. But it is interesting nonetheless. I've been diligently tracking mileage on the car during every trip to the gas station since I've had the car. Ever since I went to the 6425/Blaster SS, I've recorded about a 1 mile/gal improvement. Nothing else has changed other than changing the shocks from KYB to Bilsteins. Odd.