But if it's only chakra he'd need then control by the Sharingan would be futile cause it wouldn't be the actual fox.
It seems that Madara and Sasuke are the only two who can tame the fox, maybe cause of their Mangekyou Sharingan. Yet at the time Sasuke was inside Naruto he didn't use/have his Mangekyou ability. The fox also commented on the Sharingan being a power and chakra more sinister than his own back in episode 1.
That would be pretty awesome.Naruto needs to go get Pain's eyes.