I had a "Pacific Yew" bow that Jay made a few years ago. It was made with laminate of yew and fiberglass in the standard construction method. I would describe it more of a "flat bow" than a Hill style. Wider and thinner limbs rather than the thicker and narrower limbs of the Hill.
I would use Dacron to be safe. I make flemish twist strings and just twist the lower loop to fit snugly on the lower limb and then make the upper loop large enough to slide down the upper. If you are making an endless loop string, I think you will just have to guess as to loop size.
As far as length, 3 to 4 inches shorter than the bow length is the standard but again, it just will take some experimentation.
Arne