Gets hot and stalls out

Long thread and someone probably already covered this, but I would look for the root cause of the problem at the time that it happens. Check the fuel system for flow. Accelerator pump should squirt fuel. If not, the bowls are dry. There should be spark. If not, the problem is electrical.
As a fuel chemist, I detest ethanol in fuel. As stated, Ethanol increased the Reid Vapor Pressure (RVP) of gasoline, so modern gasoline is formulated with less volatile components to keep RVP high decreasing overall volatility and therefore hurting drivability under some conditions.
I have had ethanol fuel in Colorado dry out pump seals in a Carter High Volume mechanical pump in 3 years. They used to last a lifetime. But at least the HV Carter is rebuildable and the rubber seals are simple to replace. Just not inexpensive.
My view is that the factory in the '60's and '70's set engine operating temperature at 180°F for a reason and our older engines probably operate fine at that temp. Higher temps cause fuel percolation (boiling).
I had problems on the strip at the top of second gear all the time due to fuel issues. Just backed out of the throttle and fuel flow returned to what was needed. But it ruined my runs which was not fun.
Recently, I have had more problems with thermostats that stick. My Jeep JK was at 220-230°F multiple time until I replaced the thermostat and added a hole to allow minimum coolant flow all the time. Now it just takes a little longer to worm up, but coolant flows through the engine/radiator all the time.
I agree that checking the radiator for proper heat rejection (Lower hose is cooler than upper hose) is critical. The radiator has to function properly or all kinds of bad thing happen, including fuel percolation.
Good Luck!