Dies after 2 miles, why?

I changed the coil out for a MSD Blaster 2, and it runs noticeably better. Smoother idle, smoother cruise, fires easier, and even idled cold, a first for my non-choked TQ.

Bad news is, it is still doing it. I took my spark plug attachment that goes between the plug and the wire, and light when spark is sent to that cylinder. It definitely is NOT getting spark. It seems like by removing the cap, jiggling the wires, etc, it makes it fire back up. So it may be the pickup or the wiring, or still could be the box, or perhaps even the ignition switch?