Next time the vehicle dies perform a voltage drop test between BATTERY + and terminal 15 on the ignition coil.

If value is <.300mV I would direct my attention toward the EZL harness.

If the value is >.500mV I would direct my attention toward the ignition switch/power source.

BTW: Did you change the cap, rotor and wires? Faulty coils wires and bad distributor caps can be very enlightening on these beasts!