Thanks x24. If you are referring to the topper, it’s made from an acrylic wall display panel which came with pre-drilled holes like this one:
I dug out some old photos:
I cut some L-shaped plastic trim to size and drilled some holes to line up with those on the display panel:
The plastic trim is super-glued to the top of the cabinet and small nuts and bolts used to secure the acrylic display panel :
If that’s not what you meant, let me know.