adult sasuke can't be naruto's equal if he lacks the tailed beasts and naruto now has full kurama...lololololol
Actually.. The official Databook states that
Preta Path, which Sasuke has proven that he can use has the ability to "suck away every jutsu". The specific portion of the Databook that is interesting to note is the;
Every Jutsu, regardless of its chakra properties, is sucked away and rendered ineffective.
Essentially meaning that if a Rinnegan user can see an chakra based attack coming, then that attack is utterly and completely useless and will only aim to refill the Rinnegan user's own chakra pool. On top of that, we know that Sasuke is able to absorb and use Senjutsu without any problems. Hence, Senjutsu would also be in-effective on him. (Where as it was effective on Pain as Nagato didn't know how to control it.) That meaning, even a almost drained out Sasuke could rival a fully rested Naruto if the battle was purely about chakra based attacks.
Meaning a fight between the two would bottle down to how well Naruto can survive against Sasuke's attacks, and how well Naruto can plan his attacks and use Taijutsu properly. Which as we've seen, has been enough to render the two as 100% equals.