UPDATE: I replaced the fuel pressure regulator yesterday and the fuel trims seem to be much better. Bank 2 is about the same as it was before, but bank 1 is down to around +13% at idle from being at +30% and higher. HOWEVER, the truck still runs incredibly rough. I had to take the distributor cap off anyway to get at the FPR so I checked out the rotor as well and that all seems to be fine. The only thing that seems to be different besides the scan tool data is now when I put it in gear it doesn't die, whereas before I had to put it in neutral at stop and go lights so it wouldn't shut off. So it seems I did fix something at least? I'm still pretty stumped though. Gonna do some more digging.