[pjmoreland]

One other difference between gauge & idiot light under-dash harnesses is that the dark green wire for the temperature sensor (gauge pin 6/idiot pin 5 of the gauge cluster connector) is routed through the ignition switch on the idiot light harness, but on a gauge harness the green wire goes straight to the firewall bulkhead. The connection to the ignition switch is for idiot light bulb functionality verification when starting the engine. If the ignition switch connection is left intact when converting to gauges, then the temperature needle will peg to the right when starting the engine. I'm not sure this is a problem, but it doesn't appear to be the stock behavior. Removing the terminal with the two dark green wires from the ignition switch followed by covering the terminal with electrical tape should eliminate pegging of the needle. The two dark green wires would need to be left connected to each other.