There's a few ways to approach it. in a case where it immediately restarts, you almost need a fuel pressure gauge on it when it happens to see if it's possibly the fuel pump relay, or maybe the pump itself. In otherwords, you need a "Y" in the road to see if it's fuel related or spark related, and it's usually easiest to see if it's fuel related, so that's what you test. If you have an episode like this that last several minutes or more, you can simply remove the relay and jump B+ and the output to the pump to see if the pump then runs and the engine starts.
On the OVP relay, there is a test which involves connecting a ohmmeter to 2 of the pins and trying to move the pins and see if there is an associated change in continuity by trying to move these 2 pins.
The toughest part on yours is you say it stalls, but then will restart right away. Makes it sound more like the OVP to me, usually a bad fuel pump relay kills the engine "for good", maybe with a restart after several minutes.