Ballistics and trajectory analysis conclude conclusively the shots were fired from the 6th floor of the Book Depository. I've visited Dealey Plaza at different times, the first time within a decade of the assassination. At that time Dallas was very sensitive to what had happened and still appalled that it occurred in their city. The years went by and Dallas eventually reconciled itself to the fact and, more recently, the Museum in the old Book Depository was built ... which I visited in the early 1990's and again a few years ago.
Bystanders who were stopped on the Stemmons overpass to watch the parade were seen pointing towards the parking lot behind the bushes where this shot would have come from. They testified that they saw a person in a Dallas Police Officer Uniform run from the scene and drive off in an unmarked car. According to DPD no uniformed officer was assigned to this vantage point!
The uniformed soldier died recently but maintained his story. the Parkland autopsy was botched. The coffin that transported JFK back to Washington was flown out into the Atlantic and deep sixed after JFK was taken to Bethesda. Too many mysteries!
Get the History Channel show and watch it with an open imnd.