Intellivision FREEINTV controller support for ULTIMATE PC INTERFACE

[Bandaid Glue]

Hello, I have just set up my RP4 with Recalbox and I have to say its amazing, although I was wondering how I can use my ULTIMATE PC INTERFACE adapter with a actual Intellivision controller attached with this emulator. I have used JzIntv and it allows a hackfile.cfg which lets you use this device but I was wondering how or if I can do this with FreeIntv, thanks.!

Here is the adaptor in question:
https://intellivision.us/intvgames/interface/rev2-full.jpg