It'd be real hard to confuse either a B-17 or a B-24 with a B-29.
As I and others have stated, there's only one flyable B-29, the Commemorative (ex Confederate, P. unC.) Air Force's "FIFI". I have no idea where it is at the moment.
The only other planes I can think of that might be confused with a B-19 would be:
A Consolidated PB4Y-2 "Privateer .... the navy's ultimate development of the B-24. It just had one big vertical stabilizer (tail). A few of these are, or were, recently flying as fire bombers. The even later B-32 also looked similar, but none of those even exist.
The Boeing Stratocruiser was the civilian transport variant of the B-29, with a fatter fuselage, and was re-militarized as the KC-97, both as a transport and tanker. Perhaps some of them are still flying.
Dan Mitchell ==========
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