There is a frame for the FT5 available on grabcad.
https://grabcad.com/library/ft-5-frame-folgertech-1
and the z plate
https://grabcad.com/library/ft16-1
If you do decide to model it, PLEASE PLEASE dont do them in .stl files. They dont contain much usable information (at least in Solidworks) and most people can convert other files to .stl's easily enough.
I could make the model as well. I was just inquiring because if there was one out there in the wild, it would save me the time of taking all the measurements and doing the modeling.