Let's try some troubleshooting instead of mud slinging.

If your ignition switch is from 1973 we are all wasting out time here as this is classic symptoms of a bad ign switch. OK????

Voltage tests should be done when the car is running.

When the car is running there should be 13.8-14.4 volts across the battery terminals and 7-9 volts at the coil. Period.

Pick a ballast resistor that puts the coil voltage at 9 volts.

If you want to get technical E=IR
E being volts I the current & R the resistance

As soon as the car dies measure the voltage at the coil. 7 volts or more is what i would expect to see.

Next unplug the distributor pick up and put the leads across the terminals going to the dist. Crank the engine and meter should be changing state-ie going from OL [over limit] to a reading in ohms...Pick up is working if meter is changing state, the number is not important.

There should be several grounds from the body to the engine including one from the control box to the engine.

Post a pic of your grounds and control box set up