[tbirdtbird]

first steps to take when there is an overheat issue:
1. use a temp gun or actual temp gauge to assess what you really have, as Mitch states, motometers are notoriously innaccurate
2. be absolutely certain timing is correct and that you are running the spark rod in the correct place

"does anyone know what the air temperature itself is in the normal range when the water is normal operating temp?"
I doubt this info is known by anyone. get an IR temp gun; it is worth its weight in gold

BTW your temp differential from top to bottom of a good radiator s/b 30°

You said this is a recent problem. What is the back story? what was most recently done to the car before this began