Throwing my hands up on this ignition!

Jacobs ignitions.....measured the resistance at the plugs to calculate something...recent Ford products also measure plug feedback for turbo applications. One thing for sure: arc your wrench from battery 12V to ground, it will spark big time! Not so much with a 12V lantern battery. Amps......True. when dealing with a finite amount of volts or amps, its like f-stop and shutter speed in a camera: one goes up, the other goes down for a properly exposed picture...or whatever your electrical needs requires.