Last night I spent a lot of time crimping tiny connectors onto wires. The results are that I have proper-length wires running from power to control circuits, from the limit switches to the Arduino, and from there to the OLED display location (you can see the connector hanging there at the upper-right side of the control wiring picture below). I’m trying to avoid having to make a ground bus bar, I’ll try tapping in to the ground connections on the stepper controller board that aren’t being used.
My M2 bolts are out for delivery today. If they arrive in time I’ll have my wife bring them to me at work so I can get down to my local makerspace and install the OLED and glue in the idler assembly.