Here are the Kimberlim's in Co D, 12th MO Cav Regt (Jackson County Regiment):
Kimberlain W.G. MO 12th Cav. Co.D
Kimberlain R.S. MO 12th Cav. Co.D
Kimberlain J. MO 12th Cav. Co.D 1st Sgt.
Could J. actually be I.? Or did he go by Jefferson, and thus the J.?