Don’t forget the 20MM cannon.
I seem to recall some pilots in the pacific swapped out the 20mm for two extra .50 Brownings. As some people are aware we had to constantly adapt our weapons platforms to be effective.
I remember one experiment was done and correct me if I am wrong was a B-25 that had a 105mm ships gun that was skeletonized and mounted to fire directly forward, the pilots thought that when it fired it actually stopped forward momentum of the plane! It was used as an anti ship platform.