Little update - the condition is worsening, so much so that I can't trust that the truck will get me where I'm going anymore. While driving it is still exibiting the missing/studdering behavior (not really missing, as that would indicate a spark issue which I don't think this is at all). It has gotten worse so that now a couple times in the past couple days it suddenly bogged while driving and choked and sputtered but didn't completely die. Happened halfway to work this morning and I got off the side of the road and stopped. I smelled something which I think was the cat burning up fuel that dumped during a rich condition. I got a CEL for the first time as well this time but haven't had a chance to try to pull a code yet. The CEL went off after I started the truck back up and I was able to drive it home without it bogging again, though it was still running like crap.

I plan to pull the intake mani off this weekend and start picking everything apart: injectors (probably going to take 'em for cleaning/inspection), injector harnesses (I've never looked at that wiring but I know it is a common corrosion point), and fuel rail to check for any blockage.

I am very leary of the fact that no fuel is being recirculated out of the regulator outlet (regulator has been replaced) and I'm suspecting that whatever the reason for that is possibly what caused my old pump to fail. Could have burned up from backpressure maybe?

Anybody have any further ideas on what to look out for?