Yhe "modified" engine harness Year One sells for adding electronic ignition for a '70 'Cuda.....where do they have that set up to mount the ECU? I'd like to put it under the dash so the engine bay still looks like a 1970.

Next to the voltage regulator. It is the same as the later e bodies with the 4 pin ballast resisitor

Those harnesses are also set up for a dual field alternator.

didn't all 70s have that?