Alright, I must have been looking at the wrong source cause the one I had didn't have that folder. I downloaded the most recent build and found what I need.
I think I've figured out what I need to change to change the buttons. Now I've got to figure out how to recompile it, and then reinstall Rockbox. And if that works then I'll work on making a patch.
I'll post back if I run into any problems. Thanks!
e: I'd like to test this before I put it back on my Fuze, is there anyway I can use the Pacbox ROMs in the simulator?
e2: I just tried compiling it, and when I ran make I got the error /usr/bin/arm-elf-ld: this linker was not configured to use sysroots. I'm running Arch Linux, if that matters. Does anyone know whats up? I suspect it's because my arm-elf-gcc is 4.3.3, not the recommended 4.0.3. What can I do to get around this?
e3: I've realized that when I run rockboxdev.sh, it asks for the processor type. I've been saying ARM since it says thats what Sansa is, but doesn't the Fuze use an AMS processor? How would that change what I do?
e4: Now I'm thinking it's a problem with my export line in .bashrc. I'm not exactly sure what that's supposed to do, could anyone explain it to me? My line is 'export PATH=$PATH:/usr/local/arm-elf/bin'. Does that look right?