The east rock wall base is level now for the first course of rock to begin. We have a rock wall on the east side slope and on the west side slope with a mound of dirt in the center between the two big fir trees. This side of the lawn will have a slope going down to the road to our garden below.
We leave a big enough gap between our fir tree and the wall to not cause it any harm. The largest boulders are the base of the retaining wall with gaps for the wet stuff to drain through. 
We love the tractor, and only wish that we had purchased it earlier. It has made a lot of this work a lot more doable. There is still a lot of hard hand work to place these guys so they don’t slip around.
There is an area on the lawn side of the wall where smaller rocks are placed to help retain the soil yet still preserve the draining capabilities. 
Pry bars and gloves and Mr. Kubota are our friends for this project. 
Peter found a boulder that is perfect to recline on, so it was put on the top of the wall for anyone to use if they happen to notice it.
There are also rocks that have great prehistoric marks in them mixed in the wall. We had an archeologist tell us what this one is in-depth.
Here is the wall almost complete.