I have an acoustic Hoyer 12 string that I would like to electrify. A picture of the bridge/saddle is below. Has anyone added electronics to a purely acoustic guitar? Any tricks to it? Can anyone recommend a good but affordable preamp unit to install? Should I use a piezo? Does the unit affect the acoustic sounds? Any difference between a piezo for a 6 & 12 string? Anything you can tell me would be helpful. Thanks.