Here are the US Marine muster records for Sheridan
I suppose "Station" is a mailing address for him?
It seems like he was in San Francisco up to '45
Might have been part of a Saipan force in '46
Name: Sheridan L Peterson
Muster Date: Oct 1944
Rank: Private
Station: Second Recruit Battalion, Rechuit Depot, Mcb, San Diego, Calif
Muster Date: Jan 1945
Rank: Private
Station: 39Th Repl Draft, Casual Battalion, Marine Barracks, Camp Pendleton, Oceanside, Cal.
Muster Date: Jan 1945
Rank: Private
Station: Headquarters Company, Service Battalion, Mcb, San Diego, California
Muster Date: Apr 1945
Rank: Private
Station: 39Th Replacement Draft, C/O Fleet Post Office, San Francisco, California.
Muster Date: Apr 1945
Rank: Private
Station: Headquarters, Second Battalion, Twenty-Fifth Marines, Fourth Marine Division, Fleet Marine Force, C/O Fleet Post Office, San Francisco, California.
Muster Date: Jul 1945
Rank: Private First Class
Station: Hq, 2Dbn, 25Thmar, 4Thmardiv, Fleet Marine Force, C/O Fpo, San Francisco, California.
Muster Date: Oct 1945
Rank: Private First Class
Station: Replacement Draft "B" Fmf, C/O Fpo, San Francisco, California
Muster Date: Jan 1946
Rank: Private First Class
Station: Fifith Military Police Battalion, (Prov), Fmf, Pacific, Saipan, M I, Care Of Fleet Post Office, San Francisco, California
Muster Date: Apr 1946
Rank: Private First Class
Station: Fifth Military Police Battalio (Prov), Fmf, Pacific, Saipan, M.I., Care Of Fleet Post Office, San Francisco, California.
Muster Date: Jul 1946
Rank: Private First Class
Station: Casco, (Prov) Marianas Area, Fmf, Pac, C/O Fpo, San Francisco, Calif.