The Luftwaffe had Scharage Musik fitted in several a/c types, with both 20 and 30mm cannons. They were fitted in the fuselage of twin engined nightfighters, JU 88, Bf110, He119 Uhu (not sure of the 119 bit) [The Radio Operator re-armed them]. Also fitted to [some] FW190s [three per wing].
ALL installations were between 60-70 degrees from the horizontal.
You sat back in the bombers "blind spot"
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