Victoria Adams spoke to detective James R. Leavelle of the DPD on 2/17/64. This is part of her statement: "When the President got in front of us I heard someone call him, and he turned. That is when I heard the first shot."
I reviewed the Tina Towner film and paid close attention to the actions of JFK. In the final few seconds of that film JFK does turn his head toward the TSBD and his right arm raises up and he waves just as the film ends. Just like Victoria Adams said.
Next I used Mark Tyler"s Motorcade 63 animation and paused it approximately where the end of Towner's film is indicated. Then I plotted the location of JFK in the backseat of the limo using the scale of Mark's animation. And placed a convertible with a male character in the backseat in that plotted location (relative to the southeast corner of the TSBD) in my 3-D computer model. Next I viewed the scene (using my 3-D model) as Victoria would have seen it from the fourth floor window. The results were just as Victoria said: right in front of her window and just before going behind the tree is the convertible with the male character. The front portion of the convertible is hidden from her view by the tree limbs but the rear seat and it's occupant are still visible.
Tina Towner has said that she stopped filming just before the first shot. Dale Myers calculated that Towner's film ends just before Zapruder began filming that portion of his film. And in the first portion of Zapruder's film JFK is seen lowering his right arm just after the wave that was begun at the end of Towner's film.
I asked for and received permission from Mark Tyler to post a couple of screenshots that will let you see some of the items I used in the proceedures I have just described.
The Towner film start position:
The Towner film end position:
The view (from the 3-D model 4th floor window) that Victoria Adams was watching the motorcade from:
The free 3-D program that I use has its limitations and mine as its user. But I have used the sniper's nest model to demonstrate several things and it has proven to be accurate. I still need to fine tune things like the dimensions of the tree, but this is close enough to show that Victoria Adams was accurate in her description of what she saw. In the book "The Girl on the Stairs" by Barry Ernest Victoria clarifies her earlier statements and specifically says that she heard the first shot while JFK was hidden from her view by the tree.
Anyway, this appears to me to be further evidence that the first shot happened in the vicinity of Z-133. I believe it probably happened just before Z-133.
If any others with 3-D computer models cares to take the time to verify this work I would greatly appreciate it.