Making solid wood inserts to use in place of grills is straightforward. Download a PDF drawing of the body frame, design a shape that fits inside the teardrop-shaped frame hole, draw or print off your design at 100% scale, and double stick tape it to the wood. A coping saw works just fine if you don't happen to have a band-saw. Beware! The treble and bass frames have slightly different shaped insert holes.

Wood thickness is not critical – the hangers used to attach the wood inserts to the frame hold the back of the inserts flush with the frame’s rear screw-attachment surface, so thicker wood will just protrude further up out of the frame holes, raising the bridge with it. The neck angle adjustment allows the bridge to be raised as needed. It is convenient that cutting, carving and finishing inserts is done separately from the instrument, so that screwing up one part doesn’t screw up the whole guitar. It is a very fault-tolerant design process.