Also:

Samuel Butler, "The Way of All Flesh" (obsessed with Handel).

Malcolm Lowry, "Hear Us O Lord From Heaven Thy Dwelling Place" (long story with the hymn of that name printed in full score at the start).

Samuel Beckett, "Watt" (the voices in his head sing in polyphony and Beckett includes a score for what they sing).

I am trying to remember if James Dickey's "Deliverance" included banjos. I think they might have been added in the film.