Jim: Here is the record on that solider:
John L. Martin,Pvt, enlisted in Co D, 6th MO Inf on Jan 24, 1862, at New Madrid, MO. Transferred to Wade's Missouri Battery Sept 6, 1862. Paroled at Vicksburg, MS, July 6, 1863. Last record shows him as taking the oath of allegiance at Nashville, TN, on Jan 13, 1864.
Co D, 6th MO Inf Regt, was a southeast Missouri unit. Thus I doubt that this is the man you are seeking.