1. Coils are made of copper wires with 0.004 inches in diameter and with totally 3k ohms resistance.
2. Spools are 3D-printed. See files below to get the exact dimensions.
3. Assembly: Two coils are wound in reverse direction to each other with two button magnets placed opposite in polarity on each winding.
Electric Guitar Pickup Theory (from buildyourguitar.com/resources/lemme)