You're understanding my final goal ....but I didn't understand your question about me having access to the truss rod (which suggested I already had my guitar here in pieces) ....I was talking in general - obviously there's a truss rod in every guitar neck, but not being a truss rod expert (or neck expert), I have no idea how much space there is between the top of it (assuming the guitar is lying on its back) & the fretboard rear 'face'.

Does anyone know if there's typically a 'void' there already? (ie a gap between the truss rod & the fretboard)...these would be thin wires, though quite a few of them - about 11 wires in fact)