Hmm, *possibly these files in /pyfll/pyfll/data.
grub.kbd.cfg
grub.lang.cfg
grub.locale.cfg
grub.tz.cfg
menu.lst.cpu ?
I was suppose to mess with these this week, but life got in the way, unless melmarker has another suggestion, I will make a build tonight just to see if it can be done this way.