British Maryland utilizing the same underwing cannon as the Hurricane IID with either two under each wing, or if that is impossible, one under each wing and either two or three in as small a pod as possible directly beneath the bomb bay which would be converted for shell storage. Middlestone/Dark Earth/etc.
Attack the Panzers in N. Africa!
Gun nosed Maryland, say 20mm's, and USAF SEA Vietnam.
Coastal Command with depth charges in the bomb bay and rockets underwing.