One was on Fort Street and Livernos. It was the former Ternstedt plant. http://www.internationalmetropolis.com/2006/07/28/fisher-bod...
Fisher Body Plant 21 ---- Piquette Avenue & and St. Antoinehttp://detroiturbex.com/content/industry/fisher/index.html
My uncle worked at the Fort St. location for a time.
Your uncle probably worked at Plant 21 the East side plant