I still don't know anything about the "Old Wagon Road Historical Area," other than it shows up on USGS maps. After the ODOT/OSU Study of the wagon road, the State Trail plans changed... That study might have held some answers about this administrative area, but I don't remember anything and I no longer have my copy of the final report. Clearly, the "old logging road" mentioned below was not actually an old logging road!
As for the State Trail, plans continue to be in flux as new discoveries are made about this area... The plan above, well, not so much now. This is the old wagon road and now the State Trail cannot use it.
The discussion has moved to cutting through the cliff at the end of The Mossy Road, an HCRH style piece of engineering, and continuing the cut down the slope to the creek.
I am not sure how this would effect plans for the overlook and, in general, the new trail would run a little below the survey line I followed.
I am not sure if it will follow the old grade at the bottom, either... Could be wagon road, I don't know yet for sure.
For the "picturesque viewpoint overlooking the Columbia," see the Mossy Road to Lindsey Creek State Trail Page.