Hi, Terry,
It appears this simple to me ... from your Initial Post No. 1:
The "visible" mechanical movement of your "visible" mechanical spark handle appears to be mechanically moving a "visible" mechanical item in your distributor ...... which in turn ...... this "visible" mechanical item appears to be causing an interruption of a totally "invisible" (+) and/or (-) electrical current ..... which in turn ...... is trying to provide a spark at the (+) and (-) contacts at your spark plug gap.
As described in reply # 11 above, using an electrical testing device is one way to try to monitor the transmission or interruption of this "invisible" much needed electrical (+) or (-) current.