I don't think that is how images are meant to be used for a VM.
When I ran rancher on a VM ontop of Harvester. I used a cloud image, combined with a cloud-init to install and run rancher container. This gave me a single instance of Rancher.
This could only ever be a single instance however. Running 3 containers on 3 VMs would just be 3 individual ranchers behind a VIP and you'd get a different instance depending which one your LB routed you to each behaving as a single instance with it's own unique state. -- unusable in practice.
As mentioned, in v1.2 you can add experimental rancher vcluster which gives you a rancher instance running as containers ontop harvester's kubernetes. This is what I moved to from a VM/Rancher based solution.
Once you have rancher going, and harvester imported, then you can provision k8s clusters into harvester via rancher.