John, I'm guessing Z145 maybe?
The photo is taken by Phil Willis who is standing on the road about 2 feet from the curb just before the motorcycles arrive (you can see their reflection in the fender above the rear wheel). Since Willis was using a viewfinder camera, he had the camera up to his face. You can see this up to about z141. Then he starts taking the camera down.
He also appears to start walking backward at about z141. So it was taken before z141.
If one aligns Willis, JBC and the concrete pillar opposite, it appears to be a bit more than a car length before z160 (based on positions in Trask's map). That would put it in the late 130s:
