Pete Mahaffy was with Hawker Pacific for many years as a ground instructor and did the Pilot and engineers ground school on the PT-6, Garrets and Allison's.
Worth getting hold of the Rolls Royce book and having a read and also some of the aviation publications like Professional Pilot, Business and Commercial Aviation and the American AOPA do have very good articles on turbine engines and associated systems.
Could never figure out why Pilots only did a week on the ground school and yet the engineers got two weeks at ground school. I always put it down to pilots being twice as smart as the engineers.