School me on building a CNC Plasma!

Hey folks, I'm a hobby gunsmith, and I'm looking into building my own CNC plasma cutter table. Currently, my shop consists of almost entirely manual machining equipment, except for my 3D printing stuff, but I got my feet wet working in a CNC shop for the better part of five years before the owner, a good friend of mine, tragically passed earlier this year. I have a basic understanding on how CNC machinery operates, but I am entirely new to building my own.

My plan is to get one of the eBay gantry kits, as well as a four axis stepper motor kit, to assemble my own table.

Has anyone built a machine this way that can offer a newbie some advice?