You should use a pick and a slide!
In the top view, draw an outline of the guitar shape then use bevelplus to extrude it out into the guitar's surface...you may have play with the bp settings to get it just right. Then, for everything else, split poly and extrude or use primitives and shape them into the parts you need. Depending how detailed you're getting, break i down into individual objects...lots of little pieces on the bridge.
"Terminat Bora Diem, Terminal Auctor opus."