Throwing my hands up on this ignition!

Valkman said

Ok taking pishta's suggestions I did bit of checking. The coil read 1.4 ohms across the post and 9.8k ohms internally. Interesting the coil I changed out (an Accel) had the same readings. With the ignition on I read 12v across the coil and as 12v to the source to the Summit box. This tell anyone anything?

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12V is 12V right? Wrong! You want to get somewhere, get scientific analysis thinking happening. With the ignition sw in the run position, what is the battery voltage? Then you can compare volts into the ign sw, out to the ballast (if used), + terminal of the coil, etc. Trace the wiring. What is your running batt voltage?
If using a CDI ign the running coil + will be about 450V. Make sure your multimeter can handle that voltage as many automotive meters will not. A normal running points ign can read 100V at the coil + as the points open. This is easiest read as AC volts.It will be read also as Hz.
Are you certain the pickup in the distributor is functioning? It could be breaking down when it gets warm. Years ago I worked on a Ford with their early electronic ign that would run 10 minutes and quit. Go through the diagnostic sequence and find nothing. Next time it quit, start at step 2 of diagnostic. Finally at 3PM it stayed dead and the reluctor showed bad. Previous testing it cooled enough to test good.