Could be that Piers is hitting the traveling Cummins 24 valve electronics school. A diesel mechanic buddy in Los Angeles went to this school,paid for by his employer,a large bus company,about six weeks ago. He missed one session and wanted to make it up,looked at the schools schedule,the next week was in SF,then Portland,Seattle,Vancouver. That means it would be hitting BC right about now. My buddy said that over 200 people attended the LA classes. Also said that they are just getting Cummins 24 valves in some of their buses,before he had only worked on Detroits and Cats.
As for a mechcanic,it's not me,I have other things to do,Powershop is the place to go.