Harken headsail furling systems

We are blessed with the Harken Mark I furling system on Voltair. When we acquired the yacht, the luff of the jib was rather long, so when the halyard was winched up, the rotary swivel-block at the top was too near the offset fitting on the mast, and no tension at all was generated in the sail luff, because the one topped out against the other. Perhaps that is why we never enjoyed showers of balls in the early years of our ownership.

We bought a new jib and specified a slightly shorter luff, so we could actually tension it if desired. Since then, the top swivel has had to work under some load, and this has shown up the serious design shortcomings of this model.

Having had the cirlips pop and the balls fall out on three occasions (96 of them at about £0.80 each!), I came up with a fix that has worked for two seasons with no disasters, but with more friction in the system when you come to furl the jib.

For next season, we really would like to replace the Mark 1 top swivel with a better design, and we are told the Mark 3 fits the same headfoil (we don’t want to change the perfectly good headfoil).

Question 1: Has anyone else got a Harken Mark 1, and suffered similar problems?
Q 2: Has anyone got a Mark 3, and if so, can they tell me anything about the design of the top swivel? I’ve tried Harken in UK, USA and Sweden and nobody has a clue, since even the Mark 3 is obsolete now. If you haven’t got one, but know how the swivel was constructed, please can you send me a sketch.
Q 3: Has anyone got a Mark 3 top swivel they would like to sell? (guess this should be in the other bit of the forum)

John K