For the Pilot 2-6 Brake Electronic Brake Controller - Time Delayed # 80550 you can use Brake Control Wiring Adapter # 3035-P.
If you have factory 7-Way the only part needed to install a brake controller is the brake controller and wiring adapter. Usually the factory will already give you a brake control adapter that connects to the brake controller and plugs into the dash. If you do have this harness you can also use it with the Pilot. The OEM plug is on the drivers side, usually on the right. If the factory brake control adapter cannot be found a replacement # 3035-P is offered.
If you have factory installed 4-Way you will need a few accessories: The universal 7-Way (# 30717) or 6-Way (# 30637)
I have included a couple of links that might help below.