Driver SS agent Bill Greer's rubbernecking to the back of the limousine until Kennedy is shot, and braking at the wall corner, but then giving a lame explanation of his braking, claiming he thought there might have been a flat tire
Hoover stating in a memo only hours after the assassination, how important it was to convince the public that Oswald killed the president
LBJ's mistress testifying that LBJ hated Kennedy, and suggesting LBJ attended a meeting prior to the assassination that was possibly a briefing of events about to happen
Orville Nix claiming that his film didn't look the same when it was returned from the FBI and other signs of film/photo tampering (Were there some on site assigned to document those who had cameras and film to confiscate?)
A higher than expected percentage of deaths among those who might have had insider info, as some researchers have suggested
and etc...
It could have been a very large group of conspirators, indeed... but no one knows how large...SS agent, Bill Greer, looking back toward the president, until JFK is shot...