No...the sending unit that goes to the stocker is ONLY used for the gauge. (Driver's side, directly into lower intake.)
What controls A/F at different temps AND the fan is the ECT sensor, located in the outlet on that pipe that returns water from the heater core, and then goes back into the lower intake...that is on the pass side.
MY VOTE: OIL Pressure and Water Temp....You can tap into the SAME ground, SAME power source, and SAME dimmer source. You can even run them together through the fire wall....than branch them off to their respective sending units. I would change the oil, then replace the oil sending unit with the filter off to make it easier...just dry fit the filter first. I used a 2" extenstion fitting to give the Oil sending unit more surrounding space.
RC