Specified plug is Delco AC4 or equivalent. There is a long reach and a short reach plug. Either works. The plugs are specific for this motor. 14mm threads. Don't buy Champion plugs.

Delco R44XLS

Re E3 plug, I don't think .005 would be a no fire situation. Your issue is "No fire" not "No start". .040-.035= .005 Can you measure the plug gap of the E3?

TDC hard to detect compression stroke with hand turn.

Motor does turn over easier for starter when plugs removed.

Ignitor II has a warning about using solid copper plug wires on Pertronix? I doubt you bought those.

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