I've run the 7-pin cable along one of the A-frame members. A junction box that ties the 7-pin cable to the rest of the trailer wiring is mounted at the rear end of same A-frame member. This location will be under the floor which will provide some protection against rain. All cables connecting to the junction box will be left long enough that in the event I need to work on the connections in the box, I can unbolt it from the frame and pull it out from under the floor and easily work on it from the side.