The GO 111 indicates that the citation for his Silver Star is listed on General Order #111 for the Headquarters of the 36th General Hospital.A General Order listed all awards given to members of that particular unit, from the Medal of Honor down to a Bronze Star.Usually a Silver Star citation in a GO will tell alot about the action where he won it.
As mentioned in my earlier post, General Orders are archived at the National Archives, Modern Military Records, in College Park, MD.You can call or write them and they will send copies of the General Order.They do charge 50c per page for copying, with a minimum order of $10. So a 3 or 4 page General Order will cost you $10.00
BTW, the eight campaigns that the 45th fought in are: Sicily, Naples-Foggia, Anzio, Rome-Arno, Southern France, Rhineland, Ardennes-Alsace, and Central Europe. Assuming he fought in the last 5 campaigns, he probably joined the 45th in late spring 1944 as a replacement.