Windlass Servicing

Looking for a recommendation for windlass servicing.  We've owned the boat for almost 2 years now and the last servicing looks like it well pre-dates our ownership.  Unfortunately the 20 year old Lofrans, which functions well,  has a frozen clutch nut that doesn't want to come off & whose design makes it impervious to penetrating oil.  The next step is probably heat, which for me means a professional.  Any recommendations are appreciated.