Whats confirmed is sasukes abilities are sof6p level. The moment he started absorbing kurama said it. So it was before absorbtion took place or was completed. Now theres 2 possibilites he was at sage level and now he is above it and thats without sagemode as well. The second is he is sof6p level with 1 rinnegan with a second hed be above rokudo sennin without the biujis. Also kurama didnt say naruto hes on your level and rokudos level he said hes on rokudos level. So that excludes nardo being an equal in anyform. There are two possiblities he(naruto) is below or above rokudo(not possible since hes an idiot). I lean towards the second option because from the scan where nardo was begging kurama nardo realised hes inferior to sasuke. And without that sudden boost he would have gt solo'd instantly.and kuramas mood in way hi ts this boost makes him equal or superior in anyway.