When I turn on the lights I blow the fuse for the tail lights , dash lights, side lights and horn. I've changed bulbs , disconnected tail lights , traced wire looking for ground,disconnected lighter and it still blows. I haven't been able to find a wiring diagram for a 1992 ext. cab 4 wdr. 5.2 motor

You have a short. Unfortunately this can be a tedious task. Check the switch with a multimeter. If that does not work, you will have to start at one end on the head light circuit and visually inspect it to the end. Grab a wiring diagram to plan out your attack. Check for loose, corroded, and carbon dusted connections, frayed wires, bare wires, etc. Pay attention to areas of wire with tight, rubbing contact with the body of the vehicle. You can order a Haynes repair manual from Auto Zone or Advanced, for just about any year and model. The wiring diagrams are in the back.

You might have a short in the headlight switch itself. I would check the positive side of the taillights to see if they are shorted to ground. Not sure on a manual, besides All-Data.com. You can also purchase it thru Auto Zone.com.