Hitler's actual successor, Karl Doenitz, was pointedly not given the status of fuhrer, but only president of the Reich. But suppose things had gone to plan for the Nazis. If the Reich was meant to last a thousand years, and the Reich needed a Fuhrer, was the plan for future rulers to have equal status to Hitler?
Here's an older answer I found that you might find interesting on this subject!
https://www.reddit.com/r/AskHistorians/comments/margbi/did_hitler_have_an_envisaged_succession_plan/