Reply to Possible Midi Fighter multiplexing?

So i have a Midi Fighter classic wich i want to modify with a new case and a couple of extra faders, knobs and buttons (16 in total). Would it be possible to multiplex the inputs to 16 using one of theese?

http://www.electrokit.se/moduler-sty...bkort_41003469

And also how complex would the firmware editing be?
Im planing on using the Midi fighter in 4 bank mode.

Any help is highly appreciated!