An excellent report, Richard, and very enjoyable photo documentation. Anyone planning a summer visit to Sandia Crest should read your
surfbirds report.
I'm quite sure that the kingbird you photographed near the Triangle was a Cassin's Kingbird, as evidenced by the strong contrast between the head and throat. Cassin's' outer retrices may bleach out with wear and give the appearance of Western Kingbird's white outer tail feathers. In my experience, Cassin's have been more common than Western Kingbirds above 7000 feet elevation. Am copying a couple of other local birders for their opinion.
Thanks so much for your report and photos!
Ken