Looking at those pictures of the torso, I wouldn't cut it like on those suggestions, no offence ment but thats way too complex cut for zipper use.
How snugg is the head opening, if you try to pull your head though it as it is. Test if you can fit your head quite easily thru it, I mean when you have the torso in your hands don't try to wear it, just pop your head inside the suit from head opening and see how snugg it is.
If it doesnt need a zipper to make it open bigger, then my solution would be to cut right side seam line of the torso.
Simple straight cut from the hem part of the torso to underneath the right armpit. This will give the torso enough opening for easy suit up and chest and back areas will stay nice and zipper free. Body netting will hide zipper quite well and its not as visible as it would be if the back would have long zipper running all the way through.
I'm not an expert on this, I would quess that Termokk knows the best since this is he's torso
edit : Best way to glue zipper to latex is to use liquid latex. Almost anykind of liquid latex will work.
Simply soak all the fabric on the zipper with liquid latex and let it set. When you're cut the opening for zipper, brush thin layer of liquid latex on the area when zipper attach, wait it to cure so that latex turns to transparent. Then simply place zippers upper part in place and start to go from there. Start from the upper part, on my example case, underneath the armpit and go towards hem from there.
edit 2 : No customers at work so I had time to look around, I saw thread by maximuspred who has the same torso and has thread about it here
http://www.thehunterslair.com/topic/25119-finished-termokk-p1-torso/
Looking from those pics it looks like he used traditional backzipper running all the way up. I think he can give you an advice.