I converted a Mauser a long time ago and replaced the military trigger with a timminey trigger assembly that included a slide safety. I originally replaced the military safety lever with a lever that would function under my scope. Once the new trigger was installed I no longer needed the safety but left it in enabling me to open the bolt assembly for easy cleaning.
When I was replacing the military safety I had the bolt assembly secured in a vice and was retracting the rear of the bolt and rotating it to free it from the firing pin. I negelected to secure the firing pin. You probably know where this is going. The firing pin shoot across the room and buried itself in the wall. I can laugh at it now but wasn't then. Anyway I have been using my Mauser now for 40 years with 06 barrel. Carved a new stock for it, glass bedded it. Never had the courage to checker it.
Anyway I digress, you may still be able to purchase a modified safety lever to replace the one missing. One of the purposes of the three position safety lever was to lock the action closed. I like that option when in the woods. It keeps the bolt from opening when caught on a branch.