Alberto,
Foam would definitely make it float better. I was trying to stay as true to the original pattern as possible (reversing the direction the hackle was palmered and adding a wire rib being minor adjustments). Truthfully, this isn’t a fly I’d choose to fish with; it would need a lot of floatant or constant changing to keep it on top, and I hate using good dry fly hackle on wets. Fun to tie though and a neat study in making do with materials that were available at the time.
Regards,
Scott