We walked back over approximately the same loop, except I took a use trail I had seen from the roadway that cuts up to the electrical towers. While taking a photo of what I thought used to hold a triangular marker, I noticed another benchmark right at my feet! Here is the one below the towers, with a topo map I could probably draw a line from this to the other reference point. Of course that would mean that I actually have a map....
Also, I can now confirm the marker placed in 1957 points directly at the one placed in 1937.
Just off the road below the electric line towers - where use trail leaves the road.
Use trail I took to the towers. The fire road goes around this hill behind them from this view.
The other two markers I have seen are in a clearing at the top of this road, where it joins the main road mentioned above.
Picture of the 1957 marker pointing at the older model, next to the metal post.
"Argue for your limitations and sure enough they're yours".
Donald Shimoda