Overheated tonight: Related to prior issue?

The Mr Gasket 180 high flow TS was bad. Would not open. Air and water flow direction through radiator is correct. Visually I think I have good water flow through radiator and temp gun shows about 25-30 degree drop across radiator. I idled engine in the driveway for 30 minutes with A/C on max. The temp never got over 200. I'm not surprised since the engine never had a hot issue at idle or around town. Only hot at highway speeds. I haven't had a chance to road test again.
Auto trans using rad cooler.
Yes small 16oz overflow.
I have a good Gates hose with spring.

The radiator has a lifetime warranty so I may exchange it until my Champion CC526 comes in.

Thanks for all the suggestions.