hi ben i can speak from alot of experience tuning the k series engine and i started out with a zr105 a few years back.
you wont want the injectors as your ones will be fine, vvc ones would make it run terrible. the inlet does indeed fit but you will require get the head port matched to the inlet or else it will create a step. its also worth considering getting the 52mm throttle bodie off the zr160 to go with the inlet.
i did these mods and they certainly gave a better throttle response thats for sure, but id have to stress with doing these mods a remap is essential as the air flow etc is alot different.
i know of a place who specialise in k series remaps.