Actually, Z.1007bis cockpit is already not historically correct, it is just a placeholder, likely modified and retextured Betty cockpit with still gauges for just two engines. Anyway, I expect it should work as well in Z.506B and could be the best choice if we want to have a flyabe Z.506B quickly. Maybe there is some adaptation needed, but Z.506B and Z.1007bis seem to have pretty similar cockpit and gunner stations externally.