These are the Gs I know of:
4800-RR museum of PA
4859-Transit Center Harrisburg PA
4876-B&O Museum
4877-I think it's up around Hoboken NJ
4879-I think it is still in NJT black in NJT storage
4882-Natil New York Central Museum
4890-National Railroad Museum in Green Bay WI
4903-Age of Steam Museum Dallas TX
4909-The last I knew it was at Cooperstown Jct in NY
4913-RR MEmorial Museum in Altoona PA
4917-The last I knew it was at Cooperstown Jct in NY
4918-National Museum of Transportation St. Louis, MO
4919-Virginia Museum of Transportation Roanoke, VA
4927-illinois Railroad Museum Union Illinois
4933-NY state fairgrounds Syracuse, NY
4935-RR Museum of PA