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I made mine so the adapter was even with the bottom of the dropout, and it ended up oh so slightly loose to the wheel skewer... before I drilled, I slipped it in place, made sure the top mount hole in adapter was 'centered', bottom of it didn't protrude past bottom of dropout, clamped it using the skewer and then marked where the holes would go using a red sharpie, before I drilled and tapped it...