I need help figuring out if I have the towing pkg. or not. When I purchased Truck 2003 Ford F-150, 4.2, I was told it was included. I have a 4 pin plug, but a square hitch, it looks to be mounted on frame. I want to make sure, because purchasing travel trailer. Side sticker says I can haul 6,300 lbs. Also, do I need a larger transmission cooler or does this all come together. I have been reading some forums, now more confused. Please help!!!