Arduboat Pixhawk - Help to configure brushed motor forward & Reverse

Hi,

I’m building an autonomous boat using Radiolink Pixhawk with GPS. the FC is loaded with Ardu Rover 3.5.0

But i need to configure the motor outputs. (Brushed Motor) because i couldn’t find any brushed bipolar ESC any time soon.
I am using Skid Steering.

Issue: How to configure the pixhawk for brushed motors to connect with pixhawk for forward and reverse?