They are in the Redland area near Oregon City and specialize in Ford Powerstroke engines. A co-worker of mine has had work done on his 7.3 by these guys and has told me several times that he would not hesitate to take his rig back.
Thankfully, I haven't had any major work that has needed to be done on my 7.3, except ball joints. I had a friend of a friend who works for a truck shop do the work in his off time at his house.
Northside Ford is the "go to" dealership when it comes to Ford Trucks. I have been there to get parts several times when the local dealers didn't have them in stock.
I brought my van to Vision Diesel in Aurora. It is about 15 mins south of PDX on I5. I highly recommend them. They have a new shop and are very knowledgable with all makes especially the 6.0. Tell them Taylor sent you.
I had them do an entire bulletproof and they had it done in under 3 days.