I've seen many renditions of the GP ... they all work. This fly would be no exception, just killer !!
Colonel Drury's pattern is this:
Tail: Hot orange bucktail, over which is a small Red Golden Pheasant Breast feather
Butt: Hot orange hackle, one or two turns.
Body: Hot Orange wool, you can use seal or pig's dubbing
Rib: Oval Gold tinsel, followed by Hot Orange schallapan. Try to keep the hackle sparse so it does not interfere with the GP underwing.
Under-Wing: GP tippet feather with center removed to form a "V", tied in flat across the top of the body, extending past the butt.
Carapace: Red golden pheasant breast feather over the GP tippet feather, ending at the butt.
I often substitute the carapace feather for natural Pheasant Rump. A nice twist is a GP saddle feather (Yellow feather).
Tie this pattern in black, purple, brown, olive and mixed colour schemes from #2/0 to #6 and it would be the only pattern you need to hook both steelhead or salmon on any given river.
Really glad to see you tying Matt