Here are the mods I've done to the sight and rifle:

Streamlined the wings on the rear of the sight, removed the sharp corners, smoothed the angles, drilled the peep to 2.5mm (I tried 3mm on other sights, but 2.5 seems to be the right balance of large aperture/ghost ring visibility)

Filed and installed a dovetail steel plate to replace the missing express sights

Installed a fiber optic front sight. Once you use one of these, you won't go back to standard beads...

The fiber front is a Recknagel sight, I have several of them but am not happy with their coarsness (2.5mm rod) and fragility (they don't take direct hits kindly). I have made a stronger sight with a 1.5mm rod for a .375, and will post pictures of the one I'm making for this rifle when done.