If you don’t sail in over 20 knots of breeze you could get away with using a 2:1 ratio system for the Harken furler as it gives you a double the number of furling turns for half the effort (as described in this forum post).
However, if you do decide to upgrade, I also upgraded my boat from the Harken furler to the KZ Furler and removed the fairlead.
Like all the cleats on the Weta, it’s held in place with self-tapping screws rather than bolts, so it’s very easy to remove – I’d advise cleaning the old sealant off the screws and adding a dab of new silicon sealant before doing them up again.
Hope this helps
Paul
#325, Sydney