OK, Good to know that if you could not afford the extra expense of a coil and plugs to match,
that simply installing the dizzy would work.
However, I still think you would run into trouble sooner or later with a dodgy ballast wire or
faulty old wiring, underpowering a module that was designed for 12-14volts.
I'll go with recommending the full upgrade for reliability.
If you leave the original ballast wire in there, yes it will work, as the electronic module is designed to work in the extreme situations where only 6V might appear at the coil when starting with a near dead battery
Do also appreciate that the electronic dizzy will cause a higher current load on the resistor wire and hence actually reduce the voltage at the end of the resistor wire to lower than when operated with a set of points.
Part of using the hei coil and spark leads is being able to take advantage of setting a larger plug gap with will require the coil to maintain a higher spark voltage. At higher rpm the conventional coil will struggle, especially with the reduced voltage supply.