Gewehr 98 to K98 conversion

[Gewehr98m?]

I recently picked up a rifle at a gun show which is quite the mixed bag. As far as I can tell it is Gew.98 everything except the stock, handguard, front and rear barrel bands, and maybe some other parts. Here is a dump of pictures. I would like to know a little about the following markings I have found on it:

A small Z in a circle stamped on the safety, on the bottom when the safety is engaged (.-) and the top when it is not (-.)

And the large connection of markings on the underside of the receiver.

 

[cj556]

The safety is Czech made as the circle Z is a Brno part

 

[Gewehr98m?]

The safety is Czech made as the circle Z is a Brno part

Thanks so much! Wasn't sure if polish or Czech mark.

 

[Rutche]

The underside is factory markings. What is more interesting is receiver code barrel code, and if the stock matches and so on