I have it in Martin Aircraft 1909 - 1960.
The "XB-26E" project involved modification to four Marauders, of which three were demonstrated to senior Army officers, one with a dorsal turret behind the cockpit. A B26B-15, 41-31672 resembled an A-20 Havoc with a 37-mm cannon in the nose. Named Pistol Pachin' Mama, it had higher waist guns, four wing guns and the scoop, nacelle and rudder changes.