Sure seems like a crime of opportunity but its not hard to get sucked in by one of the many conspiracies floating around. His landlord got him the job at the book depository on Oct.15th, the actual route the motorcade took wasn't decided until November 18th. On the day of the shooting, Oswald's boss almost sent him to work at a storage warehouse but decided at the last minute to keep him at the depository. If it was a conspiracy then it involves hundreds of people.
Have you read about the theory laid out in the book (Mortal Error) that JFK was accidentally killed by a Secret Service agent which becomes even more interesting when so many close to the motorcade claimed to have smelled gun powder.
