I could not find any detailed pictures or instructions for replacing plugs on the Nitro 4.0L but I managed to figure it out. Here are some pics and information that may help others.
Overall list of tools used: Ratchet with 6/3/1" extensions, 8/10mm sockets and plug socket, 13mm open/box wrench, pliers, flashlight, shop towels, minimal cursing.
To replace the plugs you will have to remove the entire intake manifold on top of the engine:
1. Remove the four (4) hoses on the passenger side, one has two bolts holding it in. 8mm socket used for these
2. Remove the four (4) bolts holding the throttle? assembly on the front passenger side of the manifold. 10mm socket used for these
3. Remove the four (4) bolts holding the assembly to the right of the throttle? and disconnect electrical connection. Watch out for the O-ring inside as it will fall out easily. 10mm socket used for these.
4. Remove the two (2) nuts on the drivers side of the manifold that are towards the bottom, move the hanger out of the way and then remove the two (2) copper nut/bolts as well. 13mm box/open wrench used for these.
5. Fully loosen the seven (7) long bolts along the center top of the manifold. The rear most bolt is very tight fit, I used a 1" socket extension for this one as the socket on the ratchet was to short and anything else was to long. 10mm socket used for these.
Pictures listed below. More in part 2.