You guys remember this moment right?
According to the third databook, Naruto's taijutsu by the end of the Itachi Pursuit Arc was a 3.5. But this moment obviously demonstrates that he has improved his taijutsu.
Think about it, the Deva Path was Yahiko's adult body and Yahiko by adulthood should be a more experienced ninja than Naruto. But Naruto was still able to hold his own against him in a taijutsu fight.
So as of now, where would you rank his base form taijutsu skills as of now? In my opinion, at the very least its a 4.
He's definitely not at a 5 that's for sure.