In 1964 surveyors went into Dealey Plaza with instruments, ran a re-enactment, and recorded where the President's car was at fourteen specific frames of the Zapruder film. That tabulation is Commission Exhibit 884, and it is the entire measured basis for the position of that car at any moment. This model is built from it.
You can put the camera where any of the witnesses stood and see what they could see. Most arguments about that day are arguments about distance and angle, and the plaza is smaller than almost anyone expects.
It runs entirely in your browser and nothing is uploaded. Open it in its own tab for full screen.
Check the numbers yourself
The book says these measurements can be checked. That is only worth saying if the numbers are published, so they are. The geometry is one JSON file: every building, road, footway, wall, fence and tree in the model, in meters, on a local plane with its origin in the plaza.
Download the geometry What is in it
Where the limousine sits at each frame comes from Commission Exhibit 884, the survey and re-enactment the Warren Commission ordered in 1964. If the geometry is wrong, this file is where to prove it, and the corrections page records what comes back.
What it can and cannot settle
A reconstruction is good at one job: telling you what could not have happened. It closes doors. It has never told anybody why a president was killed, and it is not evidence of anything on its own. Where it disagrees with the official account, the book says so and shows the working.
How this was built is the chapter that explains the method, what it was checked against, and what you would have to do to break it.