Good afternoon guys, I've have a 2005 F250 6.0L Powerstroke. This truck has given me a headache. I'm only getting around 350psi cranking while hot and ICP is in specc. I did head gaskets about a year ago, truck ran and drove perfectly fine, customer took it and a couple days later it stalled on him while driving a couple times. He brought hit back to me, so I started off with injector o-rings and oil rail o-rings. I did find pinched o-rings on the oil rail and thought I had found the problem, but I didn't. I changed ICP and IPR with new ones and nothing, still had a CRANK, NO START HOT. Then, I moved onto replacing oil and filter with right size cap, nothing. I then replaced HPOP, stand pipes and dummy plugs, and LPOP with a new cover, NOTHING! I'm at a point right now I am beyond stumped!! Any ideas or other suggestions?? I have checked pressure with a manual gauge on the low side while hot and it gets about 7-9psi while hot cranking and while idling it is 30psi. I did check high side while hot and its still only getting 350psi and while idling it has around 550psi.