While-you-wait would not require that the item be serialzed... whether it was a gunsmith or not. To leave it and pick it up later would require it to done by a gunsmith, who would require that it was serialized so it could be entered into his book.
(This is why most gunsmiths won't touch a home build unless it's serialized)
(This is why most gunsmiths won't touch a home build unless it's serialized)


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