Electrical diagrams for Chrysler, Dodge, and Plymouth cars Electrical diagrams for 1960s and 1970s Chrysler, Dodge, and Plymouth cars, for use with alternator and electronic ignition upgrades or troubleshooting This is an engine compartment wiring diagram for a 1969 Valiant. B bodies had a horn relay rather than the horn button activating the horn directly. 1959 Intro Speeches. Seat belts Parts Needed to Add Electric Drum Brakes to a Trailer Jul 03, 2018Aside from that you need a junction box # e99011, 10 gauge wiring # 10-1-1 to reach from the junction box to the brakes, and a breakaway battery kit like part # 20400. If you don't already have a brake controller in your Jeep let