That's exactly what I had to do. When i asked this question a couple months ago no one had any answers either

We recently created a migration path here https://longhorn.io/kb/how-to-migrate-longhorn-chart-installed-in-old-rancher-ui-to-the-chart-in-new-rancher-ui/

@famous-journalist-11332 Unfortunately I am on Longhorn 1.0.0, is there a path for me?

I think you should upgrade Longhorn to 1.2.x first. You can still access the app in the legacy section. See https://longhorn.io/kb/how-to-migrate-longhorn-chart-installed-in-old-rancher-ui-to-the-chart-in-new-rancher-ui/#:~:text=You%20ca[…]%20%2D%3E%20Apps

@famous-journalist-11332 Unfortunately, It's not in the old apps section for us anymore.