Paul,
Here are photos of the sight. These sights use the rear part of a Lyman 29 1/2 and a newly manufactured base that Morris Melani designed and made.
An EDM electrode was made that smoothed the cleaning rod hole bore in the back of the receiver and also cut a small inverted 'V' at the top. The sight base spud slides in and the 'V' aligns the sight base vertically. When the thumb screw is tightened it secures the base and locks its fore-aft position.
Morris' Martini that is pictured is a two-barrel rifle and each barrel has its own sight.
