I designed this cover to fit on the Openbuilds Z-Axis standoff/reduction plate. It will bolt directly to the 4 corner holes using four M5x20 machine screws. Logo is downloaded from Openbuilds.com and cover was modeled in Fusion 360.
I am not affiliated with Openbuilds,I just like their products.
I recommend you flip the model in your slicer to print with the top against the bed (upside down) so you will only need supports under the screw holes.
Designed in Fusion 360 in inches. You may need to convert mm to inches in your slicer software.
Actual dimentions as printed: