If you want to avoid drilling the boat, then the jackplate is the place to mount the LSS2, and you can do that with, or without a transducer shield. As far as the sonar ducer, if you already have one glassed in the bilge area, then that would be the easiest one to use. If not, then your install can either be in the bilge area, or on the transom area. From my own experience of just last week, my through hull ducer quit, so I mounted one externally, but on the step as opposed to the actual transom, as in pchapins pic in his post above. I also find that now I do not lose bottom until close to 65 mph as opposed to around 50 mph with the through hull shoot. Here are some pics of some installs, including my 2d on the step. Some of these installs are Birds, but you can get the idea. Hope this helps.
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