My 1988 H35 is fitted with a pair of triple Rutgerson rope clutches. I want add another one to handle a spinnaker halyard. With some clutches, an extra unit can be added by side bolted onto the existing clutch bank. Is this likely to be a solution for me? Drilling through the fiberglass and finding and tapping into a backing plate is a daunting prospect. Where would I find an older style Rutgerson single unit that would match?