Some sad news about the passing of Gary Mack today. He was the curator of the 6th floor museum (i.e. Texas School Book Depository) and all-around nice guy. I'm not sure if he assisted SK with his book but he did with many others on the JFK assassination:
Gary Mack, curator of The Sixth Floor Museum at Dealey Plaza, and nationally known authority on JFK assassination, has died | | Dallas Morning News
Gary Mack, curator of The Sixth Floor Museum at Dealey Plaza, and nationally known authority on JFK assassination, has died | | Dallas Morning News