Well The Ford mechanic called today, and wants 3025 bucks to replace the HPOP (you guys nailed that), an ICP and some kind of elbow needed to go along with the HPOP. And he wasn't sure if this would totally fix it either, he said that there wasn't enough "pressure" to determine what else might be wrong.
I can't afford this (maybe I just can't afford to drive 6.0 Ford diesels)... I'm considering limping the truck home and letting someone else quote it, maybe another dealer, maybe some independant mechanics. I am seriously distressed about this. Thankfully, I have a back up to drive so the dealer doesn't have the upper hand completely.