If you deviate from the 9/16" bolt lug thickness, your firing pin protrusion will change. If your firing pin is adjustable, you may be able to reset the protrusion. If you have the "new" one-piece firing pin, you cannot adjust the protrusion. So you either build it so that all it takes is the barrel/bolt head swap by using another 9/16 bolt head, barrel/bolt head/firing pin adjustment using another bolt lug thickness, or barrel/bolt swap using a second bolt built for the belted magnum conversion.