I would say "you're OK." You have to understand than on any ignition which switches coil neg, such as points, Mopar breakerless, or HEI (but not MSD) you have a series circuit.........
The battery..........through the resistor..........through the coil (the load) and to ground
Voltage at the coil will depend on the resistance of the ballast, the resistance of the coil, and the RPM because it will be switching on/ off faster or slower, so think of it like duty cycle.
And of course you have to measure it with regard to changes in charging voltage
Resistors vary, and they CHANGE with temperature and current. They are supposed to, which is why they are called a "ballast."
Coils vary and Chrysler used several over the years, plus, in this day and age, you might have an aftermarket replacement.
The answer? It varies, LOL
Three things that are VERY important for voltage, and for sensing / charging voltage at the regulator is to measure voltage drop TO the resistor. This voltage drop will be greatest with the key in 'run' but with the engine off, because the alternator / regulator AND the ignition will all be drawing current.
So the "key side" of the ballast (or the blue wire on your alternator on 70 / later cars) should be within .3V (three tenths of one volt) of battery voltage.
Easy way to check this is to place one probe of your meter on the high side of the ballast, or the blue field connector (with everything hooked up) and the other probe right on the pos post of the battery.
