Bugsy,
To be completely honest, I have never done well with BWO hatches. Maybe it’s the fly; maybe it’s me; or maybe the hatch isn’t heavy enough. I have always fallen back on a Sparkle Dun pattern…sort of my answer to a lot of Mayfly hatches.
I was betting on you saying sparkle dun!
I sometimes get a little “crazy” and use Dun colored CDC!!!
I watched a guy at a show tying really tiny caddis, with a parachute hackle wrapped around the base of a hair wing. He omitted the body altogether. So it was just a hair wing and parachute hackle on a hook. It was a very simple fly and he could really crank them out quickly.