oem integrated brake controller

[mercury9]

I've been looking, searching, and trying to find out if I can make an oem brake controller work in my 2016 E450 Forester 2651S. Near as I can figure, the wiring is behind the cubby hole/coin holder. I can buy the factory brake controller, and my local Ford dealer says they can reflash the ECU to let it know the brake controller is there. But without the optional instrument cluster, there will be no place to view the setting of the brake controller. Does anyone on here or at Forest River know of a way to utilize the oem brake controller?

Thanks,
Jim