You stated you installed new plugs and it fired up. So that means everything that feeds the plug(s) are work...at that time. Have you used a spark tester to verify you are getting a good spark to the plugs? It is a very cheap device you can buy at most any auto parts store for $10 or less. It looks like this;
You simply adjust the gap to about 7/16" (it has markings on it) and see if the spark is a nice blue spark with a snappy sound. One end gets attached to a good ground place while the other end gets connected to the spark plug wire from the coil. If that snappy blueish spark is happening, all the ignition is working well. Then if/when your engine stops and won't crank, you can test it to see where the problem is occurring. And knowing you tested each part isolated by itself, you can see if you do have a temperature or moisture issue. I can see the coils being suspect before the condenser and points. You would be able to see the points with moisture on them if they were the issue. And you could then use your meter to verify parts like before. Your entire ignition system is very simple. Nothing but a straight forward setup. One thing you could check when it stops running is if the points are still set to the 0.020" setting. If the rubbing pad/block on the pints or the points themselves are moving, the point gap could be closing and not opening up. You can apply a very thin amount of grease on the crankshaft lobe to help reduce rubbing block wear with the points. JMHO
Post your results and/or more questions. :thumb: