Side 50amp plug wired wrong (Connecting 2 cabinets together)

I recently connected two cabinets together and was able to get them to function as a single system.
However, I ran into trouble when finishing the grid tied lines. one of my cabinets had their plugs wired backwards causing the system to fail as it attempted to connect to the grid.
I found and fixed the issue but it was a pain to diagnose.
I decided to make this video in hopes of it helping someone else...