I don't know anything about Carcanos, but I know this; I was in high school in 1963, and in 1969 while attending college, I met a young man who was intelligent, honest, and studying to become commercial photographer. In November of 1963 he had been working for the Dalas PD. It was his job to develop and print the black and white crime scene photographs, the Presidential assassination included. He told me that there were ALWAYS 6 photographs of every murder victim. They always followed the same pattern: top of head, left side, toward feet, right side, front, and back. Not this time. Although my friend had the entire roll of negatives, the police photographer did not shoot images of the top of Kennedy's head or of his left side. Perhaps he was coached?
Draw whatever conclusion you may.
Richard