Gets hot and stalls out

Well boys and girls...ladies and gentlemen...Damen und Herren...I've got an update. It did it to me again, but this time with a twist. As you may recall, the last time it happened the car was at 210* on the gauge while running, was shut off for about 5 minutes (temp climbed well over 210*), then started, went for about 100 yards and stalled. Wouldn't start again until it had sat for about 2 hours.

This time we took it to a car show about 20 miles away, mostly interstate. Went out there just fine (weather: low to mid-70*s, full sun). Ran at speeds of 35 mph in town to 75 mph on the interstate, absolutely no issues. Was there for several hours; long enough that the engine temp was at baseline. We left (weather: 90*, full sun), got about 95% of the way home, and it stumbled...and died. Here's the kicker: I was at about 40 mph when it first stumbled; I thought it was going to recover but it stumbled again and that was all she wrote. Engine temp on the gauge read just under 195*, so well short of the temp it was showing the last time it did this. Coasted to about 6 blocks of the house and then I got some cardio and plyometric training by pushing the car (I am far too out of shape for that ****). It has been sitting in the driveway for about an hour and it still doesn't want to start. (Oh, and it's leaking power steering fluid in the driveway, likely because I had to steer it without power and the pressure got too much.)

I've had this car for a while now in this kind of heat (and hotter) without these issues. This is literally new this year. Maybe it's not an engine heat issue after all? Lack of airflow at low speeds making it too hot under the hood? Fuel pump starting to go out? It's just strange to me that it just decided to start doing this. I'm going to continue making the changes you all have recommended, but maybe swap the fuel pump while I'm redoing the fuel lines anyway? I'm kinda getting tired of not knowing if I'm going to make it home every time I leave the driveway. And I really am too far out of shape for that kind of exercise!!