#5 coil face is 2.5mm from inside wall of air cap; measured at center of coil face in the line that passes through both holes and center post. Centerline of coil face is 5.5 mm elevation above deck lip. Cap clocking affects air hole to coil distance from 1mm to 3 mm.
the lesson was, it is really easy to go a little bigger later but next to impossible to reduce the hole without adding an eyesore. So drill slow and deliberate good luck
