The street sign that you saw, Cappinger Ave. was the name given to the road in front of the Officers Quarters and C.O. Quarters at Fort Gibson. J.J.Coppinger was C.O. at Fort Gibson from Oct.2nd,1886 to July 17th,1888. The Town of Fort Gibson was soon to start laying out streets and many of the names came from important officers that had served at the fort. To name a few, Coppinger Ave, Hazen Ln, Lee St. and other military names as in Garrison Ave, Armory Ave., Battery St. and Artillery St. I am not related to the Coppinger family.