Need help zeroing a type 3 Weaver M73B1 rifle scope

[waco16]

Not really sure as I have zero knowledge or experiences with that scope
But wouldn't the index mark be where I circled on the pic
Attachment 133797

That's exactly where the index mark is - the thing with the 'later' M73B scopes though, is that the graduations on the windage and elevation screws are on inexable plates - loosen the central screw and you can rotate the plate to zero against the index mark.
Best thing to do is to bore sight the rifle and zero to suit.
The thing I've found with mine is once its zeroed its not very accuarate to return to zero (if that makes sense) - all down to the primitive spring arrangement inside the scope