On my boat I have installed a 998 C SI external gps on the dash; an iPilot Terrova 80 universal sonar TM; HB 250C on bow connected to the TM; AS 360 SSI installed on transom and an AS ETH 5PXG all working well on my 1850 Crestliner Hawk. My question is; when I upgrade to the HELIX 12 and replace the bow using the 998' will this be compatible with the Terrova built in transducer and would a HELIX 12 come with a transducer that I could use with both units being that all is hooked up to the 5 port hub. Thanks in advance for all response.------------------------------H