His widow filed for pension in 1885, the first year they were allowed in Missouri for widows.
She confirmed he was wounded at Gettysburg, and brought back to Hagerstown, Md. where he died.

1885 Confederate Pension Applications
James M. Amos (Rockingham County)
SR_SA_1885_Pensions_Amos_James_M_Rockingham_County_04
https://digital.ncdcr.gov/digital/collection/p16062coll39/id/269/