I’ve located his actual pension application which identifies that he served in Smith’s Company A, Jackman’s Arkansas Regiment

Application for Pension
State of Arkansas
County of Lawrence

Application 20027 of W. M. Foley, Lawrence County, Approved @ $50
August 10, 1911
Served as a member of Smiths Co. A, Jackman’s Arkansas Regiment,
serving from July 1, 1864 to June 5, 1865
Note - Unable to identify the gent who authenticated William’s army service nor any information
on Jackman's Regiment

https://www.ancestry.com/interactive/60237/MM9.3.1_2FTH-1-16096-10236-93?backurl=&ssrc=&backlabel=Return#?imageId=MM9.3.1_2FTH-1-16096-7377-21

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