Replacing the plugs is fairly easy. Just remove the plastic engine cover then unbolt and remove the 4 coils. Once removed you need to look down and you will see the plugs that need to be removed with a spark plug socket.
How to change the spark plugs
u take the old ones out and replace them by color
To change the spark plugs on a 2005 Honda Odyssey, first, ensure the engine is cool and disconnect the negative battery terminal. Remove the engine cover if necessary, then locate the spark plug wires or coils and disconnect them. Use a spark plug socket and ratchet to carefully unscrew and remove the old spark plugs. Install the new plugs by hand to avoid cross-threading, tighten them to the manufacturer's specifications, reconnect the wires or coils, and reattach the battery terminal.
Screwed into the head or heads on a V6.
It is moderately easy to change the spark plugs on a Liberty, although it is rather tricky because of the gap between the spark plugs.
Sell it !!!
It is on the crank case cover. Basically on the top of the motor.
Spark plugs and wires
Changing spark plugs is relatively easy. Disconnect the batter and spark plug cables, and remove the old spark plugs. Next replace the spark plugs with new ones, reconnect the spark plug cables and battery.
Have a look at ; www.carbasics.co.uk
This is for the '05 Frontier, but should be what you're looking for. http://www.clubfrontier.org/forums/f23/how-change-spark-plugs-2005-gen-2-frontier-40507/
Disconnect the battery, remove the spark plug cables and boot, and remove the old spark plugs. Put in the new spark plugs, attach the cables and boots, and connect the battery.