I believe John Sutherland was in the 499th BG, part of the Chester Marshall crew. Thumper was in the 497th BG. Here is an excerpt from a book by Marshall.
http://b-29.org/73BW/chester-marshal...-marshall.html
In the crew photo for V-27 (Mary Ann) at the top of the page. John Sutherland is mentioned as the tail gunner and is credited with 5 victories.