Converting an older Toyota to the new 2GR means adapting a few sensors. You can either run the engine coolant temperature sensor for the factory 2GR ECU parallel with the factory SW20 coolant temperature gauge sensor or use this one sensor for both!
Running this three-wire sensor will allow you use pin 1&2 for the factory 2GR setup and pin #3 for the factory AW11/SW20 gauge read-out. This sensor will read slightly higher than the OEM single-wire sensor in both the AW11 and SW20. Note the photo for reference.
The needle calibration is can be different from car to car, so your gauge may differ slightly from the one in the photo. Often a ~30 ohms (+/-10%) in-line resistor will help correct any issues.
OEM or Equivalent Quality/Brands
Toyota Part Number(s): 89422-16010