I return! Since my last response I’ve gotten a platform, as well as a squaring tool. To be honest, I had it 100% perfect until I lifted the whole thing up from the floor, and the gantry slid around with a bit of force. The one axis is still good, but there’s a difference of .125 inches on the other. Is that negligible enough?
I’ve just ordered the wire harness so I’ve got a bit of time to kill anyways, so I can take another go at it if I have to, but I’d rather avoid it if possible.