Floyd;

Not being able to Start normally, and only by bump-Starting (when damp) suggests something is marginal in the Ignition System...the engine is only able to sustain running when the significantly more energetic bump-Start technique is used...I'd suspect HV system...start by cleaning carbon dust from underside of Dist Cap and Rotor...these can give conductive paths for HV to leak away when damp and fine condensation droplets occur...and since this would be occurring under the dist cap, would not be visible by an under-hood inspection.

I know you said you checked for HV leakage, but sometimes its subtle and not easily seen...its therefore good practice to also preventatively clean all external HV areas from Coil to Dist, to Spark-plug squeeky clean with carbcleaner as a periodic general maintenance.

COG;

Having connections clean and snug is good general advice, but it's not possible to "Verify voltage to coil" because remember, that node is strictly internal to the Ignition Switch/Armored Cable/Coil Assembly and just not available...

Good Hunting!