Both Gerben and Peter posted links to amusing 'cutaway' C96 Mausers over on The Other Forum...very interesting...
I've been trying to figure out how I would split a C96 in half. Band-sawing it is one way, I suppose, but many parts in the C96 are handened...
Milling it down would work, same problem again, and it would waste half the display...
My final solution would be to set it up in a Wire-EDM machine and let a small diameter wire run right through it...That would give you two nice halves.
Alternately, an industrial Laser could do it too. In both instances, things like coil springs would need to be removed. Grips too.
An interesting mechanical exercise...