War records are not available online. It's great that you know his service number. That makes it easier to request his service record, which would show where he served. Here is the link with more information about requesting the record:
Joseph James Savaglio, Jr. was born 20 Jun 1917 in Racine, Wisconsin and enlisted 11 Jun 1942 in Chicago, Cook, Co., IL where he lived with his wife, Marie Elizabeth (nee Mila) and her parents and sister. He was a foreman in a printing plant. Joseph died 09 Apr 1996 at the home of his son Robert Savaglio in Jericho, VT.
I double-checked service numbers since you had called him "Joseph S. Savaglio" and that service number belongs to Joseph James Savaglio, Jr.
Please let me know if you have questions about this.