The Boy Scouts, as part of a Bi-Centennial project in 1975-76, remarked the entire General Crook trail from P20 to V113.
(20 miles of trail west of Camp Verde and 113 miles of Trail East of Camp Verde)
I believe in reading about it, that this is what they used as Mile markers. Most have long since rotted and only stubs still exist. This one was in the best condition we found.