Elusive Civil War ancestor from Franklin co. AR

My grandfather's family came largely from Northwest Arkansas, Crawford, Franklin, Madison, and Washington cos. The surnames are Johnson, Elliott, Hash, Street, and Drake. One of my major brick walls is my great-great-grandfather, who allegedly died in Texas in 1865, "on the way home from the Civil War." I've not been able to find his military records, and with a name like John Johnson, you can imagine the difficulty. His wife died shortly after, likely in Mulberry, Franklin co., so no pension records. I've looked into the military records of dozens of his neighbors in Mulberry twp., and then cross checked the units in which they served for John Johnsons, but none that appear to be all likely. Anyone got any good ideas where to go next?