Uphaul:
Clutch
Downhaul: Cam cleat
Ideally, 2 cam
cleats, one either side of the
cabin top, with the downhaul running through a turning block on the pole, which (a) gives you a double
purchase, reducing strength required to pull downhaul on, and (b) allows you to
work the downhaul in conjunction with the brace (a.k.a. "guy") from the high side on both jibes
On our 40' cruiser
racer, we use 8mm spectra for the uphaul, in a garhauer
clutch. Our downhaul is 8mm double braid, in standard cam cleats. We could probably get away with 6mm for both from a load point of view, but 6mm is hard on the hands.