In these times it is really nice to read stories like this where someone does something at their own expense to help someone in need. It's a shame so many shops and stealerships charge (high) prices for procedures that are done improperly or don't fix the problem. Hopefully this shop gets more business from people reading her story.
I myself had a 03 Excursion 6.0L that had several issues (cold start, smoke, surging, oil leaks) and I took it to the nearby dealership that worked on several other Fords I owned. They gave a couple of vague diagnosis starting with EGR valve (replaced) and injectors but seemed like they were just shooting in the dark. I went to the forums and tried the Archoil fuel/oil additives that improved start up but didn't cure any other symptoms. I then went back to the forums and got many more possible answers (throwing parts) and decided to searched for a 6.0L specialist and found one I felt comfortable communicating with about 140 miles away (WI) and drove it out there. The owner took my engine apart and found many issues with parts, sensors and hoses. Interesting the common failure components (FICM, oil cooler and head gaskets) were good. I like the OP ended up spending more than the truck is worth but I replaced everything bad with Ford parts and upgraded a few others and this truck runs really good now.
Congrats to the OP for getting a long overdue solution to their problems. Some other enthusiast forums maintain a list of member recommended shops but I could not find any in other forums except sponsors. With all the 6.0l's out there it would be nice if someday there was a place where owners could look up shops based on their reviews and location.