On the 2009 F-150, it was a dummy punch out on the dash to the right of the steering column. The wiring harness was factory installed, front to back, but it required some relay up front, the actual Ford control panel, and a connector at the rea. I had a dealer finish the hookups and install the Ford brake controller. Oddly enough, for a trailer we never towed. Too much hassle. Sold it. Then gave the truck to a family member, who needed a tow vehicle.
Mike. Comments are anecdotal or personal opinions, and worth what you paid for them.
2018 (2017 Sprinter Cab Chassis) Navion24V + 2016 Wrangler JKU (sold @ ????)
2016 Sunstar 26HE, V10, 3V, 6 Speed (sold @ 4600 miles)
2002 Roadtrek C190P (sold @ 315,000kms)