I was given a Yamaha Guitalele for Christmas in 2014 (because my wife is awesome like that), and I've been using it as a fun guitar for use at home and on camp. I'm looking at playing it at church, but to do that I need a pickup. Having looked around, I rejected the locally available generic piezo pickup options, and ordered a Fishman Isys system on eBay, because Fishman provide a completely system with great installation instructions including templates for all the cutouts, and a pre-wired pickup.
Next was the battery box, with a more complex cutout. At the same time, I marked the pop for the screw holes, which I then drilled plot holes for. Meranti is brittle and tends to split of you attempt,to drive a screw without a pilot hole.
Next up is the under-saddle piezo transducer, which is installed after drilling a 2.5mm hole off to one side of the bridge, then passing it up from inside the body.
The saddle then needs to be lowered by 1.6mm- I marked off the height on both ends of the saddle, then sanded the base down until it reached the right height. All that remains is to assemble and string up.
All in all, it went smoothly, and the Guitalele sounds great acoustically and plugged in. Unfortunately,there is an occasional buzz, which might be my poor skills in setting the saddle. The Fishman set is design for a full-sized guitar, so there is a lot of loose cable rattling around inside the body, which might be also contributing to the buzz. I will probably shorten and re-solder these cables.