66 Charger no spark
 

My Charger loses spark at the coil intermittently. My car has a 383 in it and I pulled the motor over the winter to paint the fire wall. Wire harness was pulled from f/wall connection. the car has a Mallory electronic ignition with promaster coil. After reinstalling the motor the car has intermittent spark @ the coil. Wire connections at coil, appear o.k. Power coming to coil is o.k., ballast resistor is o.k.. I'm thinking its upstream but am wondering if I am missing something. Please help!