Maybe someone on here can give me an answer before I plop down $800.00. I have a Helix 7 DI (without GPS) in front of boat with transducer mounted on trolling motor. I would like to replace the Helix 7 DI with a Helix 7 SI (with GPS). But I don't know if the SI will work with the transducer mounted on the trolling motor since the trolling motor is used to steer the boat. I know they take images of the bottom in different ways and have watched a couple of YouTube videos but have not seen an answer to my question. Any help will be appreciated. Thanks in advance.