Re: changing cables
I can't speak specifically about the Bayliner, but generally If you undo both ends of each cable (one at a time) strip the nuts and rubber sealers from one end of both the new and the old cables, tape them together overlapping at least 6-8", then with a helper, start pulling and pushing the cables thru using the old cable as a "chase".
Take your time, and you may have to work them back and forth to clear obstacles, but it wont be that hard. Warning - be sure to compare the ends of the cables to verify whether the ends of the old cable are the same or different. Sometimes one end may be a little longer or have a different configuration .
Also, make sure the end of the new cable going in is the same style end as the opposite end of the old cable.
It really is quite simple as it is highly unlikely that the cables will be secured anywhere (other than their ends) and all the curves will be gradual because you can't have a hard bend without kinking the cable.
Just be sure you have a helper to blame if something goes wrong.