He is wanting to ditch the DS II and go TO points, he has the DS II now. And typically, points ended across the board on domestics in 74. 75 generally was all electronic.
I asked the question here a while back , "Would an EMP fry the duraspark". but no one knew.
I did read though, that if you knew it was coming you could disconnect any wires going to (any of ) the electronics and save them. Theory is the wires act as antennas to attract the magnetic waves that fry the electronics. Then plug it back in, and you should be good to go.
But with an EMP, you won't "see" it coming. Also, anything with an integrated, or complex circuit will likely be rendered useless, whether it is turned on/connected or not.
I don't know what the Duraspark has for circuits, I am not an electrician, and do not claim to have any electrical knowledge. Mostly all of what I say is just regurgitated from other sources.
DS II as any electronic ignition uses transistors and diodes and resistors, in essence a low power computer of a sort, so it would be useless in that kind of event. Since points are mechanical, with no diodes, chips or such, they would be fine. The condenser would be unaffected. It needs direct voltage.