If you like to y guitar, maybe you should try to do this with Guitar Hero Midi Controller. It uses well known Arduino board to interface Guitar with external MIDI device.
With the current version you can:
- play 2 octaves of an 8 note scale at a time;
- change the starting note anywhere in the range of a regular keyboard;
- change octaves’
- change keys;
- change tonal modes (Ionian, Mixolydian, Lydian, Dorian, Aeolian, Phrygian, Locrian);
- change the timbre of a sound;
- change the resonance of a sound;
- use the whammy bar to pitch bend;
- play chords in the mode you have the guitar set to (major/minor/etc.);
- rock out with a video game toy.
I think this is a great way to make your defective guitar useful. in order to make the program run, you’ll need a MIDI library and guitar library. Project is well documented and illustrated. It shouldn’t be very difficult to rebuild.