I wouldn't say it's disrespectful, but I'd bring it up with him, and explain: "You've been helpful, but the CEO role will be mine." If he balks, move on. Simple

I wouldn't say it's disrespectful, but I'd bring it up with him, and explain: "You've been helpful, but the CEO role will be mine." If he balks, move on. Simple as that. You don't have to be assume this is a huge issue until a conversation is had, and even then, if he tries to make it into a big issue you can choose to move on from him.