MSD & ignition plugs + plugs gap...

That would be a negligible ghost rider. MSD admits its there problem each time. Thank you, drive on...
I hate to say this but if you went through 10 failures out of 12 MSD boxes you may be part of the problem. When I see some guy’s method of grounding race car systems it make my skin itch. Other guys using those blue snap together wire connectors that belong in the trash cans, one ground wire connected to five different electrical devices, etc, etc.