I have a Helix 12 Chirp DI GPS G2N head unit and the trolling motor transducer is mounted using a Transducer Shield and Saver TM-DI-2 mount. Do I need the XNT 9 DI T or a XM 9MDI T transducer to replace the one I cut the cable in to. I am thinking the mega ducer since the G2N has mega capabilities but just want to be sure before ordering anything. Thanks for the help.