1/2" drive ratchet is all you need. If you can get the car high enough into the air, a 1/2" drive breaker bar might help.
Persistence definitely pays off. The plug on my car was really tough, too.
Getting the oil out is only half the battle. To get the new gear oil into the tranny, I used a funnel with a built-in flexible tube on the spout. Rather than rig something up to get the oil down to fill hole, I just bought the special funnel at Autozone.
I just ordered the redline and was dead set on doing such simple thing myself. I started pulling on the weird square bolt are realized I would probably wreck it so I quit. Took the damn car to Nissan and they did the change for $20. Just buying the funnel I would have needed would have cost $10. Take the car to Nissan don't even mention the striped bolt and see what happens.