Until you can put a real number to the temperature its just guessing.
Mechanical temp gauges are inexpensive.
Not boiling over is a good indicator of not having a problem, or not a serious one.
Thanks when I bought the car it would run up to 3/4 on the gauge so put a new sending unit in and recored the radiator and it does run cooler. Due some city driving and parades so just being cautious to try and keep temperature down.
