Leonard,
Fore-and-Aft flies really do make good midges. They seem to work sometimes when palmered versions, like the original Griffith's Gnat, don't.
A similar pattern that you might want to tie small is a Renegade; rear hackle brown, peacock body, white front hackle. For some reason that color combination really seems to trip up rainbows. We use small Renegades a lot for Tricos even though to our eyes they don't resemble the real bug in the least.