Kayser,
If the fired/
unsized case fits back in the chamber and the bolt closes, your neck sizing will not in any way hinder that.
If the fired/
neck-sized case fits in the chamber and the bolt closes, your are OK again.
If the fired/
neck-sized case does
not fit in the Wilson case gauge, do not be overly concerned as the case guage will in all liklihood
not accept a fired case unless the sides have been squeezed in via FL resizing.
If the use of a pistol case as a headspace comparator between unfired commercial and a fired cases does not reveal differences over 0.008", don't worry about it at all. Just keep neck sizing and shooting !