Hello I have a 1977 Norris craft boat with a Mercury 115 Hp on it. I have read the hard steering posts and decided I need a new cable. I looked on the steering cable and found a p/n III BIA 158-75 13FT MO969 or the last 5 are (MU969) I went into the parts section and none of the part numbers are even close to these numbers so Im not sure what to order. Does anyone have a clue. Thanks