Might have found something in the church records for Brandval, Hedmark. I looked in Brandval since Family Search showed there was a "Foss" farm in that parish.
The emigration records for this parish show a "Hans Hansen Fossmo" listed as person #31. Not sure what word is before his name. See first attachment. Could this be the person I'm looking for?
I went to the birth records for 1868 and found two Hans Hansens. The first looks good (see second attchment--person #19), but I'm not sure I can read the birth month accurately. Maybe Sept? Can you read the parents names? My Hans Hansen was born 18 Sept 1868. The other Hans Hansen is person #51 on a subsequent page, but he was born 29 Apr 1868 -- not close to my Hans.
If this is my Hans, I think I still need some extra evidence he is correct since the birth date is not an exact match.
Found some information that Hans came to the US and lived with his brother Ole Foss in Soldier, Iowa before moving to South Dakota. Can't find him in the Iowa Census records however.
Thanks for any comments...