Apparently you cannot alter the shoulders of the Elven Spellsword Plate. It shows up as 'Current part: -1' when you enter those two menu options.

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Whomst've'll'd'mn't I play:
Salema Nefahri :: A penny for your thots
Zrae'a'stra'fryn :: That which nightmares are made of
Khasir :: From the East a storm is coming

... suddenly I can craft them. I have no idea what changed, I was doing a lot of editing on it with colors. Darn.

_________________
Whomst've'll'd'mn't I play:
Salema Nefahri :: A penny for your thots
Zrae'a'stra'fryn :: That which nightmares are made of
Khasir :: From the East a storm is coming