67 318 magnum swap

68coupe said
I was under the impression that all of your sending unit and sensor information was sent to the PCM. Everything was interpreted there to efficiently operate the timing and fuel injection systems. The information was then sent to the Power Distribution Center PDC (fusebox). From the PDC the CCD bus signal (binary) was directed to the interior. I thought the CCD was deciphered there and the individual signals went to the respective gauges. I do know that most of the interior functions such as dome light, electric seats, fan motor, etc are fed by the Body Control Module (BCM).

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I did a quick look over the wiring schematics and it sure looks that way. On page 8W-40-5 of my manual it shows that there is an I/O processor that controls the temp gauge, tach, fuel, speedo, temp gauges etc...I never really looked that far into it because I kept the stock 73 instruments.
That would make sense though because the computer "knows" what the sensors are doing and the gauges would be visual representations of what the ECU knows.