I don't like using glue when attaching parts that I could foreseeably need to take apart or modify in the future, so I added screw holes for mounting the light bar supports.
The Z-Axis tops have a hole in the center of the hex depression that should have M3x4 heat set inserts (e.g. https://www.adafruit.com/product/4255) applied.
The dual mounting bars have a screw hole for securing to the Z-Axis tops using M3 screws. I used M3x12, but you could probably go a little shorter or longer without a problem.
For the change, I used Tinkercad and the modifications can be found at:
The author remixed this model.
For the MK4 dual mount that attaches via Hex holes, I added a channel through both the side bars and the Z Axis replacement tops that allows securing the bars to the printer via M3 screws.