Thanks for putting up a marabou steelhead fly from one of the most knowledgeable and gracious steelhead fly fishers I've ever been fortunate to get to know. Trey also ties this fly without the white marabou in the wing, using only the yellow and orange. And as you know, he has a series of flies tied in this style.
By the way, Trey either ties these with a nickel plated hook or lays down a foundation of flat silver floss before tying the floss body (which is almost always composed of Danville's Flat-waxed Nylon tied with a bobbin) to ensure the body "glows" and doesn't get discolored when wet. Also, he ties the wing in this manner: 1) rear most wing section; 2) first color of the throat; 3) 2nd wing color; 4) 2nd throat color; and 5) front wing color.