If you want to get really slick, buy a couple of stanchion fairleads to direct both the headsail furler (assuming you're using one) and the tack line back towards the cockpit. I don't think an actual sheave type is really necessary, as it's a very shallow angle you're inducing, and neither are normally adjusted under heavy load anyway, like sheets and even halyards (though either can have a heavy load applied - just not one you're handling constantly). I've had both of these fairleads (on the same boat), and to tell the truth, the sheave in the WL/2 seized and the rope ran over it just as well without turning, so the cheaper WL/1 with the stainless bullseye would be just fine for those lines, IMO.
I'm using a pair of small ball bearing sheave blocks I had laying around, shackled to the stanchion base, and it's not a clean installation. I just haven't gotten around to making it neater. Yet.
http://www.westmarine.com/buy/spinlock- ... 60_007_501
