Early on, before black box was used for info, LE said the gravel pulloff was 75 Ft. wide from road to cliff.
So, that could be measured from the northern entry point to the edge? There were no tracks observed, it was a confusing scene. The vehicle was stopped and then it accelerated, "pure acceleration" all the way, or something like that. Pinned to 90 but that doesn't mean car traveling at 90mph at all.
I'm driving along on Google and it looks like there is a more southern, smaller pull-off. It looks like you could sit there in your vehicle, maybe listen to some music, have a conversation, and see that fatal cliff. Maybe even decide from there to back up, reallign, hit the gas and go for it.
42360 CA-1
https://goo.gl/maps/BfDHEgtHD1U2