25 Pounder info needed.

[Private_collector]

When I recieved my package of parts from Canada, about a month ago now, there were several small parts whose purpose were unknown to me, until doing some re-reading of the manual. One Page clearly shows a rather complex device which, I imagine, is used to secure the dial sight to the upper section of the carrier. Kind of a wing-nut! A strip of metal, maybe 1.5" in length, works as a retaining piece, to prevent the aforementioned wing-nut from becoming undone to the point of falling away. Those, and the screws to put it all together, were in my parcel. I'm grateful they had been kept by the previous owner of my parts. Such seemingly insignificant pieces could easily been discarded or lost.
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I expect the spring loaded ratchet mechanism of the 'nut' (seen best in left photo below), is to prevent over-tightening, which may have caused damage to something?!?! Incidentally, it takes considerable force to turn the nut to the point of activating the ratchet.
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