The U code car in my signature is about to get a Hemi. I am pretty sure the choke cable comes through the firewall right next to the Ramcharger hoses just to the right of them.(if you are looking at it)

Anybody have a real good photo? Also I assume it is a 3/4 inch hole? The end of the cable is pretty bulky so I know it isn't a small hole. Any pics of the way it is routed under the dash?