According to the capsule histories of the 6th. Regt. and 8th. Regt. Cavalry, the 6th. was consolidated with the 8th. in the spring of 1865. Neither of these units served in Virginia.
http://mississippiscv.org/MS_Units/6th_MS_CAV.htm
http://mississippiscv.org/MS_Units/8th_MS_CAV.htm
Levi Harrington is also note here -
http://mscgr.homestead.com/MSCGRhari.html