1998 Ford Ranger Pickup Car Radio Stereo Wiring Diagram Whether your an expert installer or a novice enthusiast with a 1998 Ford Ranger Pickup, an car stereo wiring diagram can save yourself a lot of time. One of the most time consuming tasks with installing a car stereo, car radio, car speakers, car amplifier, car navigation or any car electronics is identifying the correct color wires for a 1998 Ford Ranger Pickup. 1998 Ford Ranger Pickup Truck | Stereo Wiring Diagram 1998 Ford Ranger Pickup Truck Speaker Sizes. Front Speakers Size: 6 1/2″ Speakers Rear Speakers Size: 5″ x 7″ Speakers. The following information is currently not available: Radio Dimmer Wire *If you know any of the above or any other missing information please use the comment box below to notify us.