My Elvis Blackout by Simon Crump.
I bought this book many years ago (pub. 2000) and recently rediscovered it whilst unpacking. It's a wonderful take on the Elvis myth, full of insanity and depravity. It's sort of a collection of alternative realities and situations that the quantum Elvis may have inhabited. Reminds me of Bill Drummond and Mark Manning's brilliant Bad Wisdom, which also has an underlying Elvis theme.
Love it, and due a rereading - soon.