The IVR is built in on yours. The "clue" is the 3 terminals on the fuel gauge. The third pin sends the EVR power out to operate the other gauges. So the fuel gauge has
1 terminal is "ignition run" 12V going into the IVR inside the gauge.
2 terminal is for the sender
3 terminal is the IVR power coming out to the other gauges. The fuel gauge gets power from this terminal, internally
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Ammeter? What is the question? There are only two wires in the enitire dash harness that are obvious........a huge red and a huge black, with eyelet terminals. They hook to the ammeter studs. They should be marked on the cluster, but if you get them backwards you can always reverse them.