ArduRover ASV(Autonomous Surface Vehicle) custom frame configuration in Mission Planner

I am very new to ArduRover. In fact, this is my first time building an autonomous boat. So, forgive me, if it’s an obvious question.

I am building a custom frame for my autonomous boat with 4 thrusters. It is kind of similar to the BlueROV 6 thrusters model https://bluerobotics.com/store/rov/bluerov2/, but without the 2 thrusters for heave. (This is not the final frame model. It might change after initial testings) I was reading the documentation for motor and servo configurations [Motor and Servo Connections — Rover documentation], but I couldn’t find anything for setup/configuration for a custom frame.

So, my question is this: how do I do setup and configuration for my own custom frame in Mission Planner? For example, let’s say I want to build my own boat with unique positionings of motors. What configurations do I need to do both for motors and joystick, so that when I want to move it forward via joystick, it moves forward, or when I give it a path to follow, it follows, and so on?

Any sort of help is really appreciated. Thanks.