Well... Definitely some sort of adaptation. Honest assessment, "bit crude". Sorry! Hope you can get rid of it in present receiver clutter format! Below a pix of my left side Model 94 of 1937 vintage. Offered simply as exemplar. 'Appears' a pin and the location as perhaps a cartridge guide plate left affixing pin. Just a guess but you should have some expertise soon pending.
Suggest self-help of seeking Model 94 parts-diagram on Internet! Good luck & best! John
