ZF39 Scope Questions

I currently own a byf 44 K98 rifle fitted with a SSR mount and a Carl Zeiss Jena Zielvier, serial #64000, which I understand is pre-war, with no marks for distance on the elevation turret. I understand that the military designation for both commercial and contract scopes was "zf39". Is that correct?

I have a few questions regarding the scope.

First, I tried to zero the scope and it seems not to have enough elevation. It reaches the maximum elevation internal stop. Is there any way of adjusting the internal stops in order to provide more elevation?

Secondly, being well educated in modern scopes and their usage, it is amazing to think how German snipers used the scope in battle, with the rudimentary elevation system. Did they just zero the scope and use elevation holdovers on the post reticle or adjusted their elevation turret to the proper distance markings?

I appreciate all the help on this topic, I am trying to gain a better understanding on German sniper equipment.

Heri