350 standard temp in Arizona.

[SquareRoot]

Please explain how this works. All a thermostat determines the lowest temperature the engine will run. The engine will get hotter than that depending on circumstances.

You can have a 160 and the engine might still overheat.

Agree. A 160 stat just allows the system to start cooling sooner. It does not mean it will run cooler after 160. That depends entirely on the rest of the systems ability to remove heat. In the summer, my 160 stat engine still runs at 190-210 depending on how hot it is outside.