replacement of 3 spark plugs near the firewall on 2004 Nissan Maxima

I just need to know how to replace the 3 spark plugs at the back of the engine near the fire wall

Asked by for the 2004 Nissan Maxima
Labor guide says over 2.5 hours The front plugs take .5 hours the rear plugs should take between 1 to 1.5 hours.
1 more answer
You have to remove the manifold. I'm getting the transmission rebuilt so I had them swap out the plugs while everythings out, go with iridium so you don't have to worry about them for another 100K.