I've designed the Leica-Nikon mount to be used with most Leica-R lenses, so the carved space in the Leitax mount has to allow the movement of the aperture ring from the maximum to the minimum aperture values of all lenses.
But some models have a limited aperture range and, therefore, the Leitax mount will allow the aperture ring to exceed these max and min values.
To solve this problem, I suggest this easy solution to have hard stops at the two extreme positions of the aperture ring of any Leica-R lens.

This is the plastic corner also used to glue a Dandelion chip on a Leitax mount.

We have to cut it in two halves, be careful, use a proper cutter or you will deform and spoil the corner.

Ready, we need a clean cut.

Now put the diaphragm ring to the minimum aperture of your Leica-R lens.

The R-cam of your lens will move to this position, now you have to mark the left side of the top step of the cam.
The same operation for the maximum aperture position.
Here we mark to the right side of the R-cam.
Ready, the two positions are marked.
Now remove the Leitax mount.
I use the Nexus glue
(it is a non-instant cyanocrilate)
Applying the glue at the Leitax mount and pressing the corner halves for a minute at the marked positions.

Please leave the glue to cure some minutes more before reinstalling the bayonet on the lens.
Ready, put the mount again on your lens and check the results.
Now the aperture ring cannot exceed the final F-values because the R-cam collides with our glued hard stops.
And this is the other side.
Now you can use the lens aperture ring with confidence, no risk of trespassing the final F-stop positions.

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