Ok, this is the first time posting someting on this site, but surely this thread made me go WTF!
Here is some real life physics: Lightning is an atmospheric electrostatic discharge (spark) accompanied by thunder, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms. From this discharge of atmospheric electricity, a leader of a bolt of lightning can travel at speeds of 220,000 km/h (140,000 mph), and can reach temperatures approaching 30,000 °C (54,000 °F), hot enough to fuse silica sand into glass channels known as fulgurites, which are normally hollow and can extend some distance into the ground. [source: wikipedia]
The speed mentioned before [186.000 MPH] is the speed of lightning in vacuum, almost the same speed as the speed of light.
Plus a lightning strike will try and find the quickest way to ground.
Now, in narutoverse.
Kirin is indeed a lightning attack (yeah, no sh!t Sherlock) but there are some requirements. Heat is needed to create the thunderclouds, concentration, and above all time.
Lets say that the first can happen, ok.
Then we go on the second, hmmm, I do not think so. Why? Simple actually, the fight will be an emotional one so concentration is out of the window.
But lets say that even concentration is achieved, would Sasuke manage to prepare kirin in time? Lets be real here, Sasuke will never prepare the attack in time and Naruto is not an idiot to just sit there and look at Sasuke while preparing that attack.
But lets say that Naruto did wait for Sasuke to prepare that attack by watching the later while eating popcorn, in the battle of elements Naruto holds the upper key; an attack using the wind element will nullify kirin and pretty much Sasuke will be fvcked up.
But since you chose the Bijuu Mode, do not forget that Naruto will be covered in a shroud of Ninetails' [Kurama's] chackra which in my opinion can be like Susano'o, so he can guard with that against kirin should the wind element technique fail. Also lets not forget that Naruto is very durable, so yeah, this is a plus.
Look, I could go and go and go for longer but honestly I am bored to put everything down plus everyone in here made some very good points and many more after me will make some good ones as well.
Bottom line is, Kirin will not be able to kill Naruto, end of story.