Attached is a photo before I added an end cap to the shaft and trimmed down the aluminum piece.

The shaft is a 1/4" OD threaded shaft, and the aluminum piece rocks the switches. It needs to be carefully bent to get just the right feel without pushing more than one button at a time. It floats in place when the panel layers are attached.

There's a lip glued to one edge of the underside of the filter layer to keep the aluminum piece from rotating.

I'll try to post some photos of the various other pieces if there's interest.