r/p ss141 steering cable replacement

[toxin]

hi all

my first post here. What i have is a 1984 scout bass boat 15' and im trying to replace broken
steering cable assy.

The original cable is now hard as a rock and looks like ill have to cut it at both ends to replace, however installing the new cable looks to be extremely difficult and im lookin for advise.
i am mechanically able, all the tools i need are at hand. my mechanical knowledge is in the automotive field, so expect some dumb marine questions.
the scout is fiberglass is it poss that the upper have of the boat needs to be lifted to replace this cable???

[toxin]

forgot to add engine info
50 hp evinrude o/b 1984