Dear Jim/Joyce,
There is a Tabor cemetery directory and plot map that I saw a two years ago when I was visiting Tabor. I think you can access it through the Tabor library and/or the Tabor Historical Society...contact person is Wanda Ewalt , PO Box 417 Tabor IA 51653, (712)-629-2675.

I have a photo (slide) of your grandfather's grave marker that I photographed during my very first visit to Tabor in 1978. I will have to find it, but will be happy to email a scanned copy to you. It was not a tombstone, rather a small bronze marker with a stake as I recall. I think it was located near the grave of his father, George R. Hall. It could easily have sunk as many of the markers have. There is a group "Friends of the Tabor Cemetery" who are actively working on restoring the cemetery and replacing/repairing some of those old markers and stones. Actually, I just sent a donation to them this week in the memory of our great-grandfather George R. Hall.
Karen Hall
hallpass@charter.net