I have a poor home made copy, and the 76 printed manual I had HAD is gone after the house fire. You need to scare up a legit copy of a factory service manual for your car, either digital or paper. the wiring diagrams are difficult
Here at index 51 or 51 B or C, power comes to the IVR on the PC board trace to the harness connector C1-10, from wire G5-20DBL (Wire no. G5, 20 gauge, Dark BLue)
Shows that wire at C1-24 maybe fuse 5?
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