I'm building a 6 string bass, and i was wondering if there's a standard or a common number for the distance from the highest string to the edge of the neck, and a distance from the lowest string to the edge of the neck. I wanted to build a 6 string with 18mm string spacing for more room to slap, but comfortable for fingerstyle. How would I figure out my spacing at the nut, if I want the 18mm spacing at the bridge. Thank you!