Originally Posted by BCTony
Since the radio cannot easily be reprogrammed, you would be doing the new owner a big favor by leaving the MMSI intact and having the number re-registered in his name. That's what I did when I sold my boat last fall. Pretty simple to do if you have an MMSI that was issued by Boat US or Sea Tow. Not so easy if it is an FCC issued number for a licensed vessel but that is probably not what you have.
Then you just apply for a new number if you get a new radio and program it with that number as registered to you.