5C indexing tool and miniature indexing table

[Toolmaker51]

The two pins struck me signaling start or stop positions; being symmetrical, engraving would not be all that beneficial.
And to comment "Incidentally, no hard copy plans were ever made for the device. It's purely a product of mental design and evolutionary alterations as it was constructed" proves my point exactly.
I make notes of particular dimensions needed, usually trig for setups instead of swiveling vise for example; but really enjoy working unrestricted by yesterdays or last months planning.