Thinking further on the monolithic like the prototype above.
I feel like this monolithic is something that should be pitched to Czechpoint or CSA or CNC Warrior, etc. Basically to some builder to build a "modernized" VZ58 from the start...
You don't need the front sight block and would want a barrel properly profiled for a crush washer (current/standard isn't).
All furniture, including stock, should be designed around this as well for properly eye/sight alignment -- most likely an optics with a lower than AR BUIS setup. (As you can see with the hunter, the rail and stock alignment is WAY off.)
Even that top cover on the 958, the irons are pretty much not useable... Ideally, any rail you're making for current setup VZ58s would allow for continued use of irons when the optic is removed....