1) That's an F53 Ford chassis, so you should be able to go to the ford upfitter site and find out where the brake controller harness connector is located. They're normally strapped to the steering column, but yours may be different.
2) Tekonsha should have a recommended harness for the F53.
3) The upfitter site should tell you where the nearest chassis 12 volt power is. There should be 12 volts in the tow connector near the rear axle.
FR should have some 12 volt power close to the rear of the unit that you could tap off of.
Salem 29RKSS Pushing a GMC Sierra 2500HD!
Gotta go campin!