Read post #3 above.
You shouldn't need to change the harness.

 

Dude find a good body shop to do te conversion no one I know of tat has done te conversion has used te new harness...I have my headlights and fogs wired from the 09 harness...most dealers are idiots

 

The original wiring harness will work, however, the shop performing the conversion will need to extend the fog light wires down to the bottom of the bumper.

 

What parts are needed? I'm thinking about doing the same with my 2009 non-sport but I'm not quite sure what I'd be getting into, time and $$ wise.

 

i have a 2013 g37x sedan. what exactly do i need to convert the front bumper to a sport? And do the sport bumpers come with the LED daytime running lights?

 

Anyone recommends a body's hop in miami area? I want to do this mod, but would like a reputable bodyshop. Thank you

 

what bulb does the fog light takes i want to put some led bulb in there any suggestions or comments or recommendation?

 

It looks great. I was thinking about doing the same retrofit. Was everything plug and play once you purchased all of the parts on the list? In other words, did you have to modify anything to get the parts to fit?

 

Nice job OP! Welcome to the conversion club
I did the 09 to 10+ swap. The harness bs that the dealer is giving you is just that, bs. The dealer is looking at the 10+ plug and your 09 harness and sees that the number of pins don't match since the 09 headlights have the fog lights built in. What I did was take the harness from the 09 lights and used that with my 10+ lights. The 09 headlights have an extra plug for those foglights embedded within, everything else is the same. I put hid lights in my fogs and just used the fog light plug from the 09 headlights harness and cut and extended it to my new fogs. That way you used the same harness throughout and you're basically just extending one plug. Also this allows for the factory fog switch to work just as it did.
As far as parts, take a look here
https://www.myg37.com/forums/build-t...onversion.html
This post has a very good write up, I used my old bumper reinforcement, just shaved off a bit so it wouldn't show through the bottom grille.
And look for used parts, it's worth the time

 

Looking for used part is a pain specially when you have search all over the U.S and Canada but when you get a good deal you will feel happy.
I just bought a 2010-2013 headlight for the left side for only $100 with bulb now I have to look for the right one with a similar deal, crossing my fingers.