Frame for ArduRover for boat ?!

ArduRover ArduBoat
1

Hello,
I’m using ArduRover on the Navio 2 to control a boat and I can’t figure out the best frame and configuration to control it.

My boat has two trusters (left and right), no force direction servo.

What is your configuration for a boat like that ?

Thanks.

2

Configure for Skid Steer.
http://ardupilot.org/rover/docs/rover-motor-and-servo-configuration.html

3

Thanks !
So if I understand correctly, the roll is used as yaw ?
Also during a test on a lake, the left and right direction were switched for a brief moment. Did it happen to you too ? Is it related to the gps and imu ?