All the sockets now sport channels in the bottom to capture the braid to the plate cap (whether or not the tube has a plate cap) and the wiring from the Arduino:
The Slic3r preview shows the detail a bit better:
The boss around the pins is now 25 mm OD and snaps neatly into the unpunched hub hole of a hard drive platter:
I moved the mounting holes to 42 mm OC to give the button heads on those screws a bit more clearance from the base.
Moving the knockoff Neopixel up to the top of the pipe leading to the tube base dramatically increases the amount of light going into the tube envelope:
You can just barely see a strip of foam tape holding the LED PCB (loosely) into the too-large hole.
The OpenSCAD source code also produces the improved base clamp; to get a socket, just set
Layout = "Socket" and away you go. It doesn’t yet have the reduced-diameter hole down the middle; that’s in the nature of fine tuning.