Wanted to close this out with what the resolution was. I discovered that the large power supply wire to the starter was up over bell housing just under the back edge if the distributor. Apparently it must emmit an electrical field that was interfering with the pickup and ultimate signal to the grid.

Weird thing is the 6al and 7al boxes were uneffected.

Moved the wire and it sparked perfect during cranking.

The first grid however was bad and confirmed by msd. The second I think was ok...
The third which is in the car and he drove 5 hours to get at summit Friday... He got it home and we opened it to find the fiber plug was missing!

Nonetheless... The system is now working. Keep all power wires away from grid and distributor. Luckily I just saw the wire which was in a good heat shield sheath. Moved it and bingo.

Glad that is over with!

Glad you found it. I’m curious, shielded wire non spliced to pickup? What battery cable ? No noise filter on grid ?

The cable power feed to the starter is what was routed past the distributor. This was obviously distributing the pickup from working properly.

The Violet and green wires are shielded and they were routed and changed during trouble shooting so it was not noise on them. It was the pickup which was within two inches of this cable. As soon as I moved the cable away from the base of the distributor we had clear signal and it worked. Definitely what it was.

Amazing how something like that can cause so much grief and money.

Great read, thanks for sharing. Very difficult to diagnose, lots of times you find the solution to these sorts of things by mistake.

Again great read!