I don't recall the wording on the marker and couldn't find a picture on the internet though perhaps I have one at home. It was my impression -- and its been a long time since I stopped and read the marker -- that the wording was similar to:
The Chronicles of Oklahoma: Oklahoma Civil War Sites: Bayou Menard Skirmish, near the bridge across Bayou Menard, on the south side of U.S. Highway 62. In the first Federal effort to retake Indian Territory, Major William A. Phillips penetrated to a point about seven miles east of Fort Gibson. Here on the banks of Bayou Menard (erroneously reported by Phillips as Bayou Bernard) he met and routed a force of Colonel Stand Watie's Confederates [Technically, only Taylor and his staff were of Watie's command. The "force" was two companies of Cooper's Choctaws --KM.] in a brief skirmish on July 27, 1862, taking twenty-five prisoners and killing and wounding about 100 men. Among the Confederate dead were a lieutenant colonel and three captains. Phillips was pleased with the conduct of his Indian forces in this skirmish. His only difficulty was in restraining their impetuous charge and in keeping back a reserve and guards for the wagons.
See the accompanying picture at: http://www.civilwaralbum.com/indian/menard.htm
Near the bridge and on the southside of Hwy 62 (the right side of the picture just beyond the trees which line the creek) is near where Grant Foreman placed the old Cherokee Agency. The Manard community and Woodall Spring would be NW or WNW of the bridge by a mile or more.
I'm anxious to see the article on the survey to locate the battle site.