I bought an openbuilds minimill and the electronics on the recommendation of a random forum post that I can no longer find. As my first time working with electronics I found it pretty difficult to find the wiring instructions for the Gradus M1 Pro and Bigfoot drivers. So here is the step by step series of instructions including a list of required tools and components (Excluding your CNC and stepper motors) that I wish I had before I started.
See Scotty Orr's resource and threads for previous comments on this subject. https://openbuilds.com/threads/gradus-m1-pro-information.10164/
Note: I still am researching on how to connect the PWM port on the controller to a variable speed colt router to control the spindle speed from grbl-panel. If anyone has any tips I would love to hear about it.