I was just kidding about beating you to it.

Without a picture showing the correct orientation, the area that feels like a target zone, will probably be way off at that distance. Triangulation should be the right way to land where you need. Seems like at this point, you should just take a compass reading to help keep you on track while you walk it off. Doesn't seem like declination would be an issue right now.
Rangler. The information that states it may be isosceles is already there. Three forms of numbers are present.
Three (triangle formed by drill holes),
Four (arabic formed by drill holes),
Five (arabic, set in stone).
Now, with proper orientation of the camera, to North, we may get a better perspective of which way this sleeping dog lies.
Line of sight should point in the correct direction. The distance information might be derived from the ratios rangler wrote of earlier on.
Too bad this guy doesn't know where this rock is.........or does he?