Fixed armament Lockheed Hudson
 

I am looking for some info on the twin fixed guns fitted in the nose of the Hudson.
Does anyone have pictures of the nose compartment showing the actual gun arrangement?
Also, what was the number of rounds carried and what happened to the cartridges?
Would the guns commonly be used in an anti shipping run (that would be my first guess)?

Can anyone help with my questions?

Thanks in advance
Edwin