[30 Closed Cab PU]

Other tips.
Best to do it in the shade or in the garage in low light, the led pointer is very difficult to see in high light situations.
You can check accuracy by bringing water in a pan to a good boil, measure the water, should be around 212 F, dependent on what altitude you are.
Another nice measurement is after driving for a while measure the brake hubs, if one is warmer/hotter than the others, it might be dragging, or possible bearing issue.
With Motor running measure each radiator tube in a horizibnal line across the radiator. If one or more are quite a bit cooler, you have a blockage. Repeat at different heights on the radiator.
Measure the radiator inlet neck and outlet neck to see the coolant differential.
Measure the head on the head at the base of the spark plugs, all should be close
Measure the Block horizontally across on the driver side, if one area is a lot hotter possible rust scale in a water jacket (typically cylinder 4).


Record your readings, gives you a reference for future troubleshooting.
All kinds of fun things to measure.