Nock left for a RH shooter usually indicates impact right. Right impact for a RH shooter indicates WEAK. I never pay any attention to nock left, right, high or low--only impact.
Lot of ways to tune, but I never could pull most of them off, especially paper tuning. Years ago a fell in to arrow and bare shaft impact tuning. It gives me immediate feedback. I start at 10 yards (correcting up/down first) going back 5 yards at a time making adjustments along the way. By the time I get to 25 yards I'm as good as my shooing ability allows..