Crane (XR700?) is also an option as is HotSpark. I've used the Crane and currently am using the HotSpark in my M115. I'm using the Pertronix system in my M110.

All of the three perform well. The advantage of the Pertronix/HotSpark systems are they are completely self contained and require no external additional power supply.

The Crane has a separate control unit which adds to the complexity.

The Pertronix/HotSpark systems are Hall Effect sensors.

The Crane is an optical shutter wheel.

Disadvantage of the Hall Effect type is if your ignition is left on without the engine running the pick-up trigger sensor can be damaged.

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“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.”
― Brian P. Cleary, You Oughta Know By Now