Something about the hackle proportions: If you want to emulate the Wulff's,
as tied(tyed) by Lee Wulff and Dan Bailey, then the hackle will be 1-1/2 to
2 times the gap. or roughly the length of the shank from the eye to the
bend. I'm fairly sure that Lee Wulff used the Mustad 9671 (2xl) for his
Wulffs. Of course maybe he did that because he was tying without a vise.
Personally, I don't like the idea of a gentle sloping bed of wraps in front
of the wing. The hackle will follow that slope which will angle the barbs
forward. Build up a dam immediately against the front of the wing. Encircle
the individual wings to stand them up. Then lay a smooth layer of thread in
front of the wing as a base. That way, when you wrap the hackle, the barbs
will stand straighter then with a sloped underbody.

Allan