Is this the dreaded 914 vapor lock?, Asking for your ideas and thoughts Options

[Artfrombama]

Drove my 914 to a PCA function yesterday morning, 93f and humid.
After driving on the interstate at 70-75mph for around 45 miles I exited and the motor died. I had enough momentum and coasted into a gas station/convenience store where I topped off the tank and tried to restart the car, no luck. The car would fire, run a few seconds and die then refused to re-start for another 10-15 minutes then the same scenario again. No tools to diagnose or repair.
While waiting on AAA for three hours (another story) I would occasionally try to start the car with the same results.

Today, car started normally, runs normally.

1974 L-jet, original three bung fuel pump, original location.
500 miles on new tank, sock, filter, ss lines.