The only unpleasant part was bushwhacking through poison oak in the narrow space between the river and the cliff near N 40 50.12 W 123 56.43. Enbay, do you know of a way to avoid that?
In Google Earth, it looks like there are trails/roads that go around that. Going that way would add about a mile of hiking (in each direction), and about 500 feet of elevation gain, so I'm not sure it's an improvement. And I could be wrong; maybe the lines that look like a trail aren't.
P.S.: The difficulty rating is too high; I'd call it 1.5. Once you get to the location it's an easy find.