Hi David,
I'm afraid that can't be done. The Kawai pedals are integral to the piano (Kawai Concert Artist 7) and to remove the Kawai pedals to make space for the GEM pedals would mean removing a key structural part of the Kawai chassis!
My original plan was to move the GEM pedals over to the Kawai but I overlooked the space problem

This is why I need to remap the MIDI CC values.
Mark