I have loved that Trane version for years. It was my first exposure to all the players.
When I go through the Trane Vanguard box, I wish that there were more performances like this gem. All those Indias get a bit tedious at times, and I'm kinda played out on "Impressions", especially after having played it myself dozens of times. The LP version of "Spiritual" is still great to hear, though. That bass clarinet adds such a lot, and everyone is superb on it.
When I first heard "Spiritual", I could not figure out what those chords were that McCoy was using! Then, one day, I worked it out while doodling on a piano: he was using three notes a fourth apart with a top note a major third above that (e.g. D, G, C, E) plus various root notes in the bass. This approach opens things up a lot harmonically.