I think the Reese part number is 15381. This is for a CTD with factory trailer harness. You unplug the factory wire from the back of the factory 7 pin connector and "T" this connector into it. But it only gives you a 4 wire out (ground, park, turns and brake). You will need to run an additonal wire for 12V charge and reverse lights. You could "T" the charge and backup into this Reese adaptor.
Be carefull not to short out any wires. I have heard of several cases of the power distrubution module (under the hood with the relays in it) needing to be replaced after the turn/brake wires in the trailer tow harness quit working. Not sure if it was a short that caused it, but why take the chance.