Here's a pic I found on a US site of a 474:




I'd agree with all that Gary has said about the jib and pole arrangement and bow loading. I think that I would opt for a 'floating' bow beam a bit like the present Dart 16 uses. But I wouldn't put any upward (or downward) loading on it. The jib should be attached to the spin pole and fitted with a prodder to transfer the load up to the main bridle. To make it all work you'll need a pair of wires going to the tip of the pole. A pair of wires going to the pole where the jib is attached. And finally you're main (larger size) bridle wires set above the pole by about 2ft. The prodder is an adjustable compression tube that sits beween the bridle wire and the pole at the point where the jib attaches.