on a worn cylinder there is never any wear in that spot, why can't he just chamfer that and run it? the rings dont go down that far. or if it needs pistons map the ports out, resleeve that cylinder and report it?
you guys need to be nice to this kid, if you look at his profile he doesn't even know how old he is,or where he lives, or his birthday, they all say unknown. so please help him nicely.
they should be 8mm x1.25
it happens, get Time Serts they are way better than helicoils, or drill and tap it for a bolt two sizes bigger red loctite that in cut it off then drill and tap it to the oridginal size, works great just a little more work but worth it
what oil are you running? and is the adjuster tight and centered in the pressure plate correctly? the sticky gear saver oil wil make a clutch creap like that