Are there any write-ups with photos on replacing it? I've searched. How about the Updated part # and a good place to purchase it?

Patient: 05, 160,581 miles. Cat and Muffler delete about 6/7 months ago looking for better fuel mileage, didn’t get any. Other then that it’s completely stock. I did just put the updated Fuel Pressure Regulator kit on it about 300 miles ago due to a flatted keyhole gasket.

Symptoms: No DTCs, Will not start when hot. Really Sluggish acceleration until about 1,800 rpms then it’s runs like normal.

I have a sinister EGR Delete kit I bought about 5 months ago ready to go on. I bought it when my 06s EGR cooler burst. I figured I would do it when the temps cooled off this seams like a good time.

 

6.0 Liter Ford Powerstroke - High Pressure Oil Pump & Revised STC Fitting Part 1 - YouTube

This is a great video by a Ford Sr. Mater Tech on the process. I believe there are other videos that go with it.

Have you been able to check your ICP voltage and/or HPO pressure and IPR duty cycle? Sounds like you're on the right path, but would be good to confirm with some gauge readings.