The nut is a 2-7/16" (62mm) long piece cut off from a
5/8x3/8" (15x10mm) aluminum angle. Drill three 3/32"
(2mm) holes into the 3/8"(10mm)-wide side as shown in the
drawing above. Align the nut to line "B" and fasten it
with three tiny screws. For this I used the same screw type as for
mounting the tuners. Pre-drill the screw holes with a 1/16"
(1.5mm) drill bit.