This is another one of those repairs that is counter-intuitive...nowhere near as simple as it looks. The drain plug must be exactly straight, not something that can be done by hand. Miss by a tiny fraction of a degree, and you'll have a chronic oil leak to fight. These threads are going to see more action than any others on the bike, no bandaid/kludge repair is going to last long. You'll have to drain the oil & pull the motor to do any kind of thread repair, regardless. Just take it to a machine shop, where a precision repair will be routine work. I'd use a Helicoil. You'll get a solid, undetectable, repair for the <minimal> extra effort of hauling the motor to a pro. Afterward, pull the clutch cover, lean the engine over toward the RH side and hose-out the metal filings with solvent. They'll be trapped in the chamber with the oil screen. The outer clutch cover will be even easier to clean, off of the motor.
This would be an ideal time to clean the oil spinner, while the clutch cover is off...killing two birds with one stone.