Since the bore-up finished well, I purchased the bearing exchange around the lower back crank for replacement. Though there are three fixed clutch cover packings on the photo, the actual one comes with both types of fixed ones. It is safe and made of Kitako of the body.
I would like cheaply selling the price of the crankcase gasket only. The washer of the drain bolt is smaller than the bolt diameter and can not be used. (Insane) I want an explanatory diagram of usage except crankcase gasket. There is no explanation as to where Oring is used.