What I love is how PKD and Horselover Fat phase in and out of each other throughout the book. Near the beginning, PKD makes it clear that Fat is "him" and that he's narrating the book to give himself clarity on the events. But then PKD the narrator slowly instatiates into the story as a completely separate character. There are scenes with Dick, Fat, and his friends all talking. And then that changes again later in the book.

I see almost 4 versions of PKD in VALIS: the narrator, Fat, the narrator instantiated into the story itself, and then the real life author (who is treating this book as semi fictional, semi autobiographical).