Dave, yes, that part was identified many years ago!.I'm sure this has been mentioned before, but I don't see it on any of the part maps. Maybe I'm looking at the wrong ones.
On the FALGA Panel, there's an exhaust cover from the 1:35 Nichimo Tiger II. Inside that, I believe, is the machine gun port from a 1:48 Bandai Tiger I.
Sorry, if I'm posting something already known.
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