My daughter had a Hannah Montana party for her 4th birthday and wanted a guitar cake. I knew I'd never be able to shape an actual cake into a guitar so I used cupcakes instead. I was a little rushed so I didn't get to look at an actual guitar, I just fudged them together till they looked right. I'd say its a mix between the body of an acoustic and the pickups of an electric. Plus it only has 4 strings, LOL, but she didn't mind.
The Happy Birthday words look AWFUL but I have bad arthritis, so I blame that =)
I put it on a piece of foam board that was covered in wrapping paper and star confetti.