May be it is so late for your request, but perhaps you still need some information.
I think you are interested by the network layer and how you can add some routing protocols in NS2 based on the ACO . If so, you can take a look in this chapter in the link, i can provide you some piece of code if you need it.
Oh yes please if you can help me with it especially with the coding part.I was looking to implement some wireless routing protocols based on ACO in VANETS. Please if you can help me with it.