I'm curious... (sorry if I missed this earlier in the thread)
After the truck died... will it crank?
Edit: In re-reading the original post, I see that it DOES crank but won't start.
Also, as I recall, one *can* attach a new PMD as test, just to see if it's the PMD which has failed. In other words: Plug in a new PMD (no need to mount it fully just for a test) and see if the engine fires up. I'll admit that I'm going on "gut feel" here, but if the engine just died completely like that, I kinda doubt it's fuel related. If it was a fuel quality or fuel supply issue, I *think* it would sputter and try to run, but fail.
If the truck died completely and WILL crank but not fire back up, my first gut instinct is the PMD being dead, or I suppose (I think this was suggested earlier) maybe the neutral safety switch cutting in and out when it's not supposed to?
Either way, I'm honestly just thinking out loud as a former H1 owner who's forgotten a lot about how to diagnose these amazing beasts