[RedBarchetta]

Bad ground on an MSD box shouldn't cause a pop. When the MSD box goes, or the ground goes, you lose all ignition and there's nothing to light off unless your plugs are glowing red.

What conditions did the pop/die situations occur? Acceleration? Cruising? Slowing down? Could be as simple as a misadjusted (too high) float level, or debris in the fuel line that is hanging up the metering rod in the float bowl.

-Dean