Which version do I need

A little bit of background Ive been reading post in the forum for over a month, Im more confused in some ways now than I was in the beginning. I understand the concept, thats a start.
Here is what I hope to do with AOG section controll for my sprayer 3 section boom 20 foot each
guidance as in light bar field mapping.
and I would like to have the option to add auto steer.
Note I do not own any tractor with can bus, so if I go auto steer it will be motor driving the steering wheel.
So my question is which version should i download to use and which pcb do i need to use.
Thanks for the help.

You could go with the latest stable release, machine module usb ino, a arduino nano with a screw terminal breakout board, a relay board and an ardusimple f9p gps receiver.

This will give you a cheap lightbar guidance rtk capable with section control.