I would suggest file fit plasma moly rings & dingleberry hone with a 320 grit flexhone. Follow their instructions on drill speed/# of strokes/duration/feed rate (up/down angle) & they even say on their site that any light oil is OK. Sure they'd like you to purchase their oil but WD40 works fine. If it is a rering be sure to cut the ring ridge which takes alot of care when useing the ridge reamer. Pull the cutters toward you with a 5/8 box wrench & change positions many times around the block for good leverage & frequent checking as to not cut past past the ridge cuz it dont cut dead even all around the circumference