I have a 1199 on the bow and minnkota fourtrex with US2 but as I understand i still need the side image transducer to use SI as it won't work with us2(correct?) If I run a splitter to have both plugged into the unit, which transucer works? Can I pick a transducer in the settings? Or should I just scrap the us2 and use the side trans? Ideas?? Thanks!