This Job is pretty Straight forward, if you have an OBD tool to read the Toyota Automatic Transmission Oil Temperature or a good quality thermal imaging camera or non-contact infrared temperature gun to read the temperature of Fluid between 35C to 45C when the adjustment in fluid level is made.
Thermal imaging camera being pointed towards Automatic transmission oil pan, you can expect 2 degree C difference in oil temperature and oil pan temperature with oil pans temperature being 2C below the actual ATS or Toyota WS oil temperature.
verified from OBD kit while using non-contact temperature gun and thermal imaging camera side by side.