I recall messages/discussions on the Sheeley family. Apparently it wasn't this thread, but from discussion i ended up tracking down a Sheeley descendant. It was Jim Feldhaus, grandson of Frank & Mary(Sheeley) Feldhaus. I'm guessing it was well over 5 yrs ago, but in the phone conversation I found Jim really interesting, with lots of family stories. I especially recall him telling about "Marshall" Sheeley. I would suggest you try contacting Jim. He was, and is still listed as living at Canistota, SD. His phone # is available on Whitepages.com.
I am not a relative, but do genealogy work, particularly at Howard, Miner Co, SD. Photos of all the gravestones in Miner Co, obviously of Sheeleys' included, are online at www.southdakotagravestones.org