If you are worrying about string spacing at the nut then I highly recommend this tool from Stewmac:https://www.stewmac.com/Luthier_Tools/Types_of_Tools/Straightedges/String_Spacing_Rule.htmlKeeps things simple…(it was a lot cheaper when I got mine yrs ago! – but I would not be without it) Mark in 1/8″ (3mm…   Read more»