Creating New Rancher Hosts without Internet Access, Using Private Registry

I found the the Rancher documentation for ‘Launching Rancher Server with No Internet Access’. However, I have not found documentation on creating new Rancher hosts in an environment without access to the Internet, and a private registry is used (Artifactory in this case). I have tried repacing the ‘rancher/agent’ in the new host command with the path to the same images in our private registry, but Rancher still tries to create the hosts using ‘rancher/agent’ and ‘rancher/agent-instance’ images. Any help woud be greatly appreciated.