Hopper/caddis/stonefly/meat. The original appears to have been built on a foam sandwich oriented in the horizontal plane (I guess they bisected it dorsi-ventral to achieve the split legs); tried it here in the vertical plane. Downsized here for trouts.

hook ? Dai Riki 300 #8
thread/rib - UTC 140 burnt orange
underbody - dubbing rust
body/head- 2mm foam rust
flash - Krystal Flash orange
hackle - grizzly dyed orange (1Tbs Rit Sunshine Orange/1 cup water)

Part 1

Take foam strip (gap width - probably a bit too wide; maybe 80% next time), fold in half to crease, brush Super Glue on first 1/4? or so, fold and hold until the glue sets; cut to shape, tapering underside at front and back

Mash barb, start thread, wrap to bend

Dub thread/dub underbody

Tie on body

Tie on KF

Tie on (folded) hackle by tip