Building a levelling jig (no replies)

I've designed a leveling jig that will hold a dial indicator and level the table within a few thousands of an inch for some really awesome prints, but I need a copy of the X shaped mount in a .dxf format so I can edit it to fit leveling nuts to replace the stock ones.

Is it possible to get a copy of that in a format that I can modify it? I don't have any software that can work with .stl files (I use RhinoCAM).

Or is there any decent software to convert mesh to .dxf?