Check out any of the twenty Left Crankcase Cover / Alternator components enlisted.
Some items from this specific schematic: Gasket,cover L (nas), Bolt,flange,6x35, Screw,pan,6x12, Bolt Flange,ubs 1.
The Bolt,flange,6x35 is the most widely applied product in the CB450SC NIGHTHAWK 1985 (F) USA CALIFORNIA LEFT CRANKCASE COVER / ALTERNATOR ( five times ).