Yep, it's just a blower motor power source and nothing else. Looks like somebody didn't learn their lesson in 2002.
The PCM could be bad, but it's pretty rare for an NGC unit to die intermittently -- or at all for that matter (that was JTEC's job).
The NGC controller has one quality that JtEC didn't have; that it doesn't become unconscious if the 5v feed to cam, crank, MAP, TPS is shorted to ground. The engine will still likely die, but a trouble code or ten should be generated and it'll remember it. JTECs just take a nap and wake up wondering what happened.
So, with no codes stored and fuel pressure good, my speculation machine is running low.
Can you describe what it feels like when your truck dies out?
Or more gradual, as if you were losing the fuel pump (as you described).
Is it a linear drop to nothingness? Or does it recover and retreat?
Does it matter how much throttle you give it? Like... does it improve or get worse with more throttle?