My confusion...what I meant by "dial it in" is to have the controller accessible from where you can monitor your GPS speed so you can visually set the controller to desired GPS speed. I did not think these things hooked up to your GPS but I guess someday this will be NMEA 2000 ready and you'll be able to do that.
Adrien -- for your installation was it easier to run the power line for the Troll Master all the way to your dash? For me it probably makes more sense to run the wire directly to the battery thats only 3-4 ft away.