Not a whole lot of info on this fly; possibly originated along the Gallatin in the 40's. Precursor to the Goofus Bug, Horner Deer Hair, etc, which sired the Humpy.
hook - Mustad 9671 #6
thread - UTC 140 black
body - chenille yellow
tail/shellback - deer hair
hackle - grizzly
Part 1
mash barb, start thread; tie in rib and wrap back to bend
strip end of chenille, tie in, wrap to front
clean, stack, measure (tips shank length past bend) a clump of deer hair; trim butts/tie in