How to sew 1/6 zippers?

I was transplanting the old 1/6 sniper wolf onto a new kumik body when I realised that most online pics shows that her shirt/body suit is actually zippered rather than buttoned. (guess they changed designs after 10+ years?)

I also happpen to have an old IM2 black widow jumpsuit which I was planning to throw away. (It tore at the area around BW's bewbs... THEY CANNOT BE CONTAINED!!!)

In this case, is there any way I can "transplant" the zippers from the BW suit to the old sniper wolf uniform?

Do I sew it on by hand? Inspection of the BW jumpsuit showed that the sewing is REEEEEALLLLYYY fine and nearly non-visible. How the hell did they do that?

They did that with training and experience. All I can say is try it. Be prepared to pick it off and redo it if not satisfied. A seam ripper will cut the stitches without damaging the material. Probably be a lot easier by hand, with a thin needle. I use a beading needle for jobs like that--need a microscope to thread it (almost).