Dates may be off here; K-510 (42-108489) was a maintenance trainer at Keesler and was burned in a firefighting demonstration at an Armed Forces Day airshow circa the late '40s. Note the nose fairing; it probably never had a turret:
viewtopic.php?f=3&t=55492&p=550112&hilit=dominator#p550112Per this thread, the one destined for the museum was 42-108474 which was scrapped at Davis Monthan in 1949. The XB-32 at McClellan was probably burned in '51 or '52, making it the last survivor:
viewtopic.php?f=3&t=53756
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All right, Mister Dorfmann, start pullin'!
Pilot: "Flap switch works hard in down position."
Mechanic: "Flap switch checked OK. Pilot needs more P.T." - Flight report, TB-17G 42-102875 (Hobbs AAF)