Greg, it's a dedicated, soft stay made from Dynex Dux and attached to the mast with a t-ball fitting (into a socket). The bottom end leads aft to a two-part purchase dead-ended next to the cabintop winch, with the tail brought through a clutch to the winch. It needs to be a fair lead - I blew up a clutch when I first tensioned it.
As Justin implies, the strength and rigidity of the deck is critical. If your existing track is for the spinny downhaul/foreguy it won't be strong enough and the load will damage the cored deck. If the track is for a baby stay it might be okay, but you really need to transfer the load down into the hull like I did. Unless you have a Valiant 32...
This setup was intended for a solent, not so much for a storm jib, and it turned out the existing furler compromises the program. When you get the solent stay tight enough to be able to point, the furler is sloppy loose and you can't roll/unroll the sail that's on it. So it's a two-stage process to get some tension and hoist the hanked-on sail, then roll the sail on the furler, then tension the soft stay fully. I was still not able to get sufficient tension to point normally with the solent, plus the rolled-up sail ahead of the solent causes some drag.
I did all this several years ago and haven't messed with it since, but I'm talking to North about the big picture and maybe going to hanked-on headsails exclusively. There are various attachment options besides traditional hanks - my #4 attaches with soft hanks for example.
Fun stuff but the boat is pretty good now and at some point you just have to stop...
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