Trying to install a cheap'o autozone brake controller in my early 99' F250. I was told there is a pre wired harness already under the dash and all I need was to buy the harness adapter kit and plug it right in. The only two open plugs I see under the dash are a huge gray rectangle one and a...

Hi guys, and gals... I just bought a '06 F250 PS CC LWB which I need for some mild towing. Unfortunately it doesn't have the upfitter (sp?) switches and the brake controller in the dash. I possible can both be added if I get them, with all the wiring harnesses and the fuse block?? Any input...