Re: Optimal halyard length?
Dropping the mast is not a big deal, especially if you have a mast tower/crane at your marina. Your boat is over 40 years old. If the sheaves and brass bushings are original it's probably time for some new ones. Get an eyeball on that mast head and you will know for sure what you have. That said, I would get rid of the wire halyards and replace them with line and properly sized sheaves. Depending on the type of sailing you do, I don't think you need the high-tech Dyneema type line. Just some good old fashioned Sta-Set is cheaper, will hold knots and will work fine for years to come.