The taillight and headlights blow when you rev up the engine

check the trailer harness if your truck came with trailer package those harnesses are known to go defective. do daytime running lights work?

GOOD ADVISE--I ALSO LEARNED THAT THERE MAY BE FUSES IN UNDER THE HOOD ALSO. FOUND OUT TODAY THAT IF THE DOME LIGHT DON'T WORK THEN IT'S FUSE COULD BE BLOWN AND HINDER THE CIRCUIT TOO. I'M NOT GOOD ON VOLTAGE READING , BUT DO HAVE A TEST LIGHT. IF NO FIRE AT THE COMMON TAIL LIGT-DASH LIGHT FUSE , THEN THAT MIGHT NARROW IT DOWN. I HAD THE SAME TROUBLE IN MY 1990 FORD XLT LARIAT AND WAS BLOWING THE TAILLIGHT FUSE. IT WAS A SHORT IN THE EXTERNAL TRAILER KIT HARNESS WHICH CAUSED FUSES TO BLOW REGUARLY. WHERE IS RELAY FOR TAILIGHTS AND OTHER FUSES UNDER THE HOOD??

Usually indicates there is a wire shorting on the lighting circuit somewhere.
check all existing wiring for chaffing or water getting into the electrics
Hope Thgis Helps

Take rear lamps out of their sockets and turn on power if fuse still blows more than likely its a wire. Did you check the TAG LIGHTS, and side marker lights?

check the parking light fuse or taillight fuse to make sure it has not blown. replace it if it has blown and see if the lights work or if the fuse blows again. if it blows when you turn the lights on then you have a short circuit that needs repaired. if the fuses are good ,then most likely the headlight switch is bad not allowing the taillights or dash lights to work.

No taillights and the headligts blow the fuse when turn on would indicate that there is a wire failure with the tail lights and when the headlights, being on the same circuit, are turned on, the fuse blows because there is a short in the tail light wiring.
Good luck

The taillights are commonly connected to the dash light circuit ( so you can be aware when they do not work ).
Start with the fuse box. Read carefully for the correct fuse to change. Sometimes they have a strange name associated with them. Turn the lights off before you change the fuse otherwise they may blow even if the circuit is OK. If it blows again you need to look further to find a shorted wire. ( Most likely in the boot, near the taillights, a wire has been crushed or damaged.

Check the fuses. Look at the Amps given to the lights. It could be lower.

Check the electrical grounds for the taillights. In fact, get a diagram and check all the easily accessible grounds. Many of these are in the engine bay.

Dan