Just picked up another boat (2002 1800 ProV Tiller) and am now looking at updating the electronics. I plan on having one dedicated Side imager and one for 2d/DI and gps. Open to suggestions on Humminbird or Lowrance or a combination of both. My main question though is the command center on the tillers. Do the internal GPS units work inside the cabinent? or will I be searching for something that has an external GPS? Does anybody even make external anymore?