The first time you go to do them it's a mission. Once you have done them once they are really easy and can be changed in less than an hour.
Well I just had to change some plugs on a Hyundai coupe v6 for a friend and what a mission that is!!
Front 3 are easier than the zs's but the back 3.....
You have to remove the throttle body, disconnect everything from the inlet manifold, remove the inlet manifold just to get to the plugs. There are blind bolts at the back to undoand not a lot of room. I would rather change the Z's plugs a hundred times than do that again!!!
on another note, it was an 03 plate and had a tonne more rust than my zs did and that was a 51plate. I miss my car