The pattern I've used from Caucci and Nastasi for the nymph stage is this,
Tails and legs- amber dyed wood duck (i use mallard 'cause thats what I have)
Body- olive-brown dubbing
Wingcase- black (i use dyed ringneck tails)
Thread- black (I'm sure any dark thread would work)
Hook- size 10,12
They also suggest using a standard hares ear wet fly for an emerger pattern instead of the traditional quill gordon wet recipe. I'd bet either pattern works.
Lastly in Hatches II they suggest that the nymphs make less effective imitations during actual hatching activity and that the emerger (wet fly) pattern is more productive. "However, between 10 A.M. and midday, the nymphs expose themselves while migrating to favorable hatching sites located on the lee side of obstructions in the fast water where they become available to trout who root for them in this area."
If you haven't checked it out, Hatches II is a great reference for tying to match specific hatches. Good luck.