Should be in the battery compartment for the trolling motor batteries. I have the 1875 pro guide, they should be in the bottom of the rod locker. You might have to pull the batteries out to find them. Mine has 3 red wires with breakers ( positive ) and 2 black wires ( negative) . The smaller red one is for 12 volt to the rear for a Vantage. Should be wired like this for 24 volt. 2 big red to 1 positive, jumper from negative of first battery to positive of second battery, small red wire to positive of second battery if using a Vantage. Both big black to negative of second battery. I think all the pro guides are wired that way. If your using a regular rear trolling motor you don’t hook up the small positive.