I think he's trying to have Naruto side with him not kill him. Get Naruto to go along with his plan so, he has to prove himself by showing he can kill Naruto even though theyre bros.
He can be this kage and Naruto the traditional one and then they'll fight both as Kage
That's what Naruto meant in the last chap not beating him as he is now but when they've both accomplished their respective goals as kage