Have been inside a b17, very cramped with a thin walkway up the middle past the bomb racks and side gunner ports.
Taill gunner has to crawl down a tiny tunnel to get seated, belly gun ball has a very tiny door to get in on the top, talking to the staff
i was told that you had to be thin and no more than about 5 ft 6 and flexable to get in, bomb racks a tiny and hold not a lot, not one bit like the movies.