The 6000and the 7000 are the same generation, seatalk
interface. The 7000 had 2 more features that are rarely used, and more buttons. Your biggest problem is going to be the installation
where the 7000 was wider, so the 6000 will possiblyhave unpainted surface to the right of the hole.
You might not even have to do the settings. If you check your current
settings, and see if the new unit sees them too. (Rudder gain, max deflection, rudder
alignment, displacement hull
, etc...) RTFM.