Here's the post asking for help:
Here's the source and solution:
Most of the replys were pointing toward the spark plug wires or boots (pin holes or carbon tracked. Three mentions of dialectric grease and one suggestion that maybe a bad brain box.
The wires and boots seemed in good shape and I had never heard of dialectric grease, (wasn't used on the original boots). Turns out that moisture around a couple of the boots *was* the problem. The source of the moisture was a leak around the thermostat housing. If I accelerated fairly hard it would flood the two plugs right behind the thermostat.
Whenever it missed I would wait for it to cool down before checking it out and by that time it was dry enough not to catch attention. Replaced the O-ring and cleaned up the housing but still had to add a bit of silicone to completely reseal the housing. Pretty crappy design IMO. Thanks again to all who replied. One to file away?
Frank