Welcome! What are you thinking of building? The terminal boxes look ok. You really need to ask yourself if the machine is going to be portable? Does everything need to connect permanently or are plugs of some sort needed? If I watch the forums much, I want to build stuff like the best fabricators here have. Of course do I need it? Do I even understand how it works? Or how to use what I have to the best of my abilities. The best idea is to get started. You will always see a better way to do it but you have to have a starting point. Enjoy and again welcome.