I am getting ready to run my main halyard to the cockpit on a Hunter 23 the line is long enough and I have all the parts. I have a 2 line turning block Schafer and a 2 line spinlock rope clutch. I read about what to use to seal the equipment, of course i failed to write it down. I do know when I drill the holes to be careful of the ceiling material so I do not rip it off the ceiling. I also read to ream the holes out and put epoxy in the holes so it seals the core. I need to tape the underneath before I poor the epoxy. WHat I do not know is what kind of epoxy. Once that is done I redrill and set the fitting. What I do not know again is what to use under the fitting 4200 or something else. I have a role of butyl caulk but not sure that will work. If that does work, do I need something else also?