If your grandfather was wounded or received an award the quickest way to narrow it down (Company) is to check honor roll and awards rosters in these two books. IF he is not listed you get a great historical reference that might be useful for additional research.
We Ripened Fast: The Unofficial History of the 76th Infantry Division Hutnick, Joseph J. Book Description: Frankfurt, Germany: Otto Lembeck, 1946. Hard Cover. First Edition. Folio - over 12" - 15" tall. 249 pp., illus. (color & b/w), maps in color, awards roster, honor roll/KIA roster.
76TH INFANTRY DIVISION (ISBN:1563110482) Turner Publishing Co Staff Book Description: Turner Publishing. - 128pp - The proud history of the "Onaway Division" from its activation to its sweep across Germany is chronicled by compelling first person accounts and poignant photographs. The story of campaigns in Rhineland, Ardennes-Alsace, and Central Europe are eloquently told with a narrative filled with maps, charts, and historical text. Indexed with roster.