Rigging humminbirds?

[musher92648]

Hey Guys,
I have a new to me 96 Yarcraft 1990 Michigan that I will be transferring my H'birds to. I put a Terrova w/Ipilot and US2 on it and I would like to utilize the ducer on the Terrova. I have a Humminbird 997 SI and a Humminbird 787 c2i. On my old boat I had both transducers mounted on the transom and that worked OK. I got better readings at moderate speeds with the 787 and would use the 997 when at slower speeds or actually trolling. So my questions are how would you rig this to take advantage of what I have and what do I need to make it work in the way of cables etc.?
Thanks,
Lloyd