Vexilar
Sorry I didn't update this. I have retired all those fish finders and by far, and we have installed them all, the best solution we have found is the Vexilar system. We shot the transducer through the hull by the jet where the hull is single layered, run the power right off the battery and mount the WIFI box, well in the case of Yamahas up front in the cuddy and Seadoos in the glove box. I then run my phone or Tablet off the WIFI signal in combination with the Navionic software for GPS etc, and budda bing your in action. I had a customer tell me that all cell phones are coming out water proof now, even better than my water proof case. I mount the phone or the tablet in a RAM Mount made for the model of device you have and mount that into the Maverick bracket system and your done. I'll send some pictures eventually when I get a chance, I have video for the Wave Runner install and the Seadoo install, just been too busy.
Here's a cool thing, the sonar app from Vexilar is a free download, so your buddy can see your sonar and you can see his, I can see the day when the information will be combined for a multi view overall combining everyone in your groups sonar together creating a area pattern, anyway, that's the easiest install, no holes blasted and simple as spit.
Oh and another thing before I forget, the Vexilar software monitors your battery voltage and gives you an alarm if your wearing out your welcome, get fishin faster.