when SO6 path created 9 tails out of biju chakra
there might be a chance that has he put his own chakra split among 9 tails.
Which will be used when the 9 tails willingly unite for the good cause.
In case of naruto they all gave him some kind of power willingly(it can be possibly assumed its SO6 path chakra from each one)
i mean if minato can include his own chakra in kyubi.. why cant SO6 path.. after all he was the one with great vision split the 9 tails and also left the information to his descendents about how to revive 10 tails. also he did inform the bijjus at the time of creation that a day would come when you all will unite once again.. He would have kept his own chakra in case of disaster..i dont expect to S06 Papth to be revived..(if orochi and kabuto didnt get S06 body till date only means that he has hidden his own body far from edo tensei..or would have self destroyed:P)
another kind of proof to support this is when as now kyuubi and naruto are friends and when kyuubi/naruto swicth .. that chakra around has close resemblence silhoute of SO6 path we have knows so far.. (when naruto fought kyuubi and extarcted chakra without kyuubi's will.. the resemblence was much lesser comapre to kyuubi willingly giving it) May be when he activates all tailed powered chakra on course (if the intial assumption is true) . we may get to see S06 path to guide him to fight juubi/anything equivalent.
I also believe the fully assembled chakra of the Bijuu will give Naruto an encounter with the Sage of Six Paths, as well as potentially some power boost or key knowledge.
i hope naruto doesnt get another power up , as he is now , he is already overpowered , sage mode is slowly becoming redundant and i would have preferred if he had trained with alot of risks to get the kyuubi power instead it feels like a cheap extremely over powered power up although i hope we have an encounter with the sage of six paths but not an edo tensei one