Oh it was super easy. It takes just a few minutes. Mines a tekonsha Prodigy P3. Great controller. Mine has the 7 pin connector(the round one) but I have an adapter that can go to 3 pin. The adapter is definitely the way to go. Re routing stuff is just too complex especially if the adapter costs $7

 

So you were able to use the factory harness and just plug the adapter into it, thus making it a 7 round? I just want to make sure nothing short circuits, and the electric brakes work on the trailer. Thanks for the reply.