Doing more research on B-25 straffers found when Pappy Gunn did the first B-25's with 4x .50's in the nose and 2 x .50 twin packs on the fuselage sides, they wanted to step up the firepower so a 20mm cannon was added to the nose armament situated in the lower left nose , A B-25 of this configuration was flown by Maj Ralph Cheli (MOH) on his last mission, this cannon installation was eventualy removed as it was found it was to hard to harmonise the .50's and 20mm to each other- a fact I thought strange considering the standard armament of a P-38 was 4x.50's and a 20mm cannon , also latter in the war as pacific bomb groups traded in there C/D model for new J models , the J models had glass noses with a bombaimer they still wanted staffers so added 2x.50's to the left side of the nose, to match the 2x .50's on the right side of the nose plus the single .50 in the middle on a pintle mount, plus 4x .50's now in single gunpacks 2 on each side of the fuselage, I would hate to be the bomb aimer in one of these with 4x .50 going off beside me and 4 more going off behind me and still try and fire the single .50 or drop bombs! as the factory 8 gun noses become available the glass noses were replaced the bomb aimer gone and most units also got rid of the 4 single gun packs from the fuselage sides , less drag , 8 guns was consided enough and weigh saving with 4 .50's and ammo removed, I don't think many other aircraft in the war had such variations to armaments fitted as the B-25, from 1 x .50 and 4x .30 in the A thru multi .50's, 20mm and 37m cannons to 75 mm cannon thru to 18x.50's in the J model, and bombs, rockets, torpedo's and missiles.