I need a huge favour done, just to check the wiring.

Pull the 4A/T fuse, and tell me what it does to the instrument cluster. Note that this will "limp home" the transmission, as it will detect an electrical problem.

The other one is can you tell me what is operational when the ignition is in accessories mode. Clock, lights, etc.

Reason being, I still have to sort out those extended wiring glitches.