Well, for a few reasons:
For starters, you can't simply change the tuners. The Nylon Series tuners require a different size hole for the capstan than is required for the steel string slot head tuners.
The NS32ce nut width is 1-7/8". A 314ce is 1-3/4".
The NS32ce heel is going to be too short, because the GA body is deeper than an NS32ce body. Ergo, the holes for the neck bolts on the neck heel won't be aligned with those on the body.
The NS32ce neck meets the body at the 12th fret. On the 314ce it's the 14th fret.
Technically, yeah, you could affix the NS32ce neck to a GA body, but it would be unplayable...