Aircraft certification is, well, peculiar. And believe me, modifying a delivered aircraft is nowhere near as easy as "install that certified box", because said

Aircraft certification is, well, peculiar. And believe me, modifying a delivered aircraft is nowhere near as easy as "install that certified box", because said box has to be compatible with the aircraft you want to install it on. And as I said, no idea how US-only aircraft differ, hardware and software wise, from their European airspace brethren. Do no, it is propably not as easy as going into maintenance mode and set a toghle from 2 to 25 hours on the voice recorder firmware.