And then marking the side tangs

Masking tape is wrapped around the mast at a perfect 90° so that all tangs are at precisely the same height... 15 foot 2 inches, only two inches higher than design, though the designer allowed a higher deviation. This is so the foot of the jib clears the console I added on the cuddy top, with a little room to look under, barely. Use a light punch tap so the drill bit doesn't wander. Use the standard recommended size bit specified for that size tap (these are 10-24 threads)!