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On a practical side, crimping three wires on a terminal is not going to work well.
So you may find the ECU power wire tapped in at another location.
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(Factory harnesses with electronic ignition usually have a splice tap starting around '72.)

Here's a general scheme of the 5 Pin ECU wiring.
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ECU harness wire colors will vary.
(based on Fig 19-3 in the MP/DC Speed Secrets collection of bulletins)