A few years ago I bought a 3-position safety from Pacific Tool and Gauge and had it installed by a local gunsmith on myZG-47. At the same time, I had him install a Timney Sportsman trigger. The combination worked flawlessly.
The safety shipped with installation instructions that includes details of modifications to the bolt body, the cocking piece and the firing pin.
https://pacifictoolandgauge.com/mauser-performance/1030-mauser-m98-three-position-safety-shroud-kit.html?search_query=Mauser&results=78
https://pacifictoolandgauge.com/material-downloads/boltmod/mauser98-safety-install.pdf