Hi Paul,
As you can see in the video and pictures, the Lowrance is mounted under the starboard coaming. There is just barely enough room here with the included low profile pivoting mount. It is a safe and out of the way spot to put it, although much easier to see on a port tack.
From here, the transducer wire runs aft under the side deck, out a hole in the aft coaming, then forward again through the coaming in between the hardwood blocks for the mizzen step. This was done because we already have a pile of wire running aft of the coaming for the solar panels installed there, and it keeps the cockpit looking cleaner. The wire then runs down the coaming behind the mizzen, and follows the surface to the transom. It goes out the aft end of the motor well through the slotstrip, and is mounted on the transom with the provided bracket. The shoot-through transducer would have some advantages, but this mounting was simple and we knew it would work.
For wiring runs, we used a kit from Weld-Mount which comes with a two part acrylic adhesive and a pack of mounting pads that let you attach wires with zip ties. This worked out great, and the adhesive stuck to our topcoat with no surface prep.
I agree that the plotter/sonar combos from Lowrance are great units, don't know why you would need anything more for recreational navigation. The Navionics chart card we purchased for the US is quite detailed and accurate, not to mention affordable.