Most all parts are available. depending on serial number, some parts superseded to newer style parts
not to difficult, take t bar assembly out , remove chaincase top cover, remove connect links, remove all chains
remove cluster sprocket inner nut & outer bolt, then drive sprocket shaft out or in to remove, later version has to 2 matched bearing sets with preload rings (4) Bearings total with a spacer in the center, early version only had 2 bearings total