What would neck width (at the nut and body end of the fingerboard) be for a six string bass with 5/8" string spacing at the bridge? I realize tapering will vary so what's a typical rule of thumb for the nut end? One half the string spacing at the bridge? I'd like to know the same info. for 16mm and 16.5 mm string spacing. (carvin 6 string spec.) and 17mm, please. For every mm added to the string spacing, how much wider will the fingerboard/neck increase? I'm fairly hopeless with decimally based measurements. I do understand mm or fractions of an inch. Thank You!