It looks like if you restored the /APL/iGo folder on your avic with the one on your backup and then installed GTIMatts mod it should work without glitches. It'll keep the icon theme and sound changes, too, although you'll have to do the software bypass yourself.
edit:
To clarify a little bit: if two mods change the exact same files, or if they change completely different files, you're fine. Anything else, and you should restore first.