Beyond Frustrated - Wont start/stay running

OK, very good and glad you checked the lead resistance and accounted for that. The ballast sounds decently good at 1 ohm cold. And the coil is the right primary resistance to use with a ballast of this range. And OK, on the points gap; that verifies the dwell reading that you were getting.

The yellow spark does sound weak, and this could cause the poor running. Is the coil a new coil? If so, what brand/model?

Next, with your meter, measure the resistance of the coil wire, and then all of the spark plug wires. They typically will be in the range of 5000 to 10000 ohms, (5k to 10k).

Also, measure the voltage at the coil + when cranking.

And I am not clear: when you tested the condensor, did you actually mount a new one inside the distributor? And did the new condensor have a value, like so many 'uF' ?

Is the distributor clean at its base and touching clean metal in the block? Are the points screwed down properly? (Probably are...)

I am just thinking of all the ways in which the spark could be weak, some of which are uncommon issues.