Chevrolet Repair: headlights, fuse box, wire connections

Question
my father has a 1978 chevy k10 i believe a 327 motor..maybe 350...but all of a sudden his headlights quit working. at same time he was having issue with dimmer switch...we replaced dimmer switch...headlights not working....replaced headlight switch today....still no headlights....all other lights work..i found which wire from headlight switch powers headlights....i bypassed it and ran a wire straight to headlight to make sure bulbs arent blown...they still work...appears to me that power stops at fuse box...however i have checked all the fuses and they are fine....i am at a loss of what to do...any help will be greatly appreciated sir

Answer
HI RONALD,WELL YOU WILL NOT FIND A FUSE FOR THIS BECASUE THERE IS A CIRCUIT BREAKER IN THE HEADLIGHT SWITCH ITSELF. SO WE CAN RULE THIS OUT. IT SOUNDS LIKE YOU DID SOME DIAGNOSTIC WORK ON THIS YOURSELF. YOU SAY THAT YOU BY PASSED THE HEADLIGHT SWITCH AND RAN A NEW WIRE TO THE HEADLIGHTS ??? SO  HOW ABOUT YOU HAVE A PROBELM IN THE WIRING HARNESS FROM THE HEADLIGHT SWITCH OUT TO THE MAIN HARNESS ??? IF YOU HAVE POWER GOING OUT OF THE HEADLIGHT SWITCH FOLLOW THIS WIRE TO THE FIREWALL BULK HEAD AND CK FOR A CONNECTION PROBLEM HERE..IF NO PROBLEM THERE KEEP GOING TILL YOU FIND A BREAK IN THE WIRE OR PLUG CONNECTION THAT IS CORRODED OR JUST OPENED UP. USE A 12 VOLT TEST LIGHT WHEN CHECKING HIS WIRE..JUST MAKE SURE YOU HAVE 12 VOLTS COMING INTO THE SWITCH. ONE SIDE WILL BE HOT AND THEN WHEN YOU TURN THE SWITCH ON YOU WILL HAVE POWER GOING OUT THE SWITCH...I AM NOT AT WORK SO I CAN NOT LOOK THIS UP ON MY COMPUTER FOR THE FLOW CHART OF WIRE CONNECTIONS AND COLOR WIRES.SORRY..BEING THE AGE OF THIS TRUCK IT WOULD NOT SURPRISE ME IF THERE IS A CORRODED WIRE CONNECTION OR A PLUG ALONG THE WAY.LET ME KNOW HOW YOU MAKE OUT AND GOOD LUCK TO YOU,. HAVE A GOOD HOLIDAY..I WILL BE HERE THUR IF YOU NEED TO ASK MORE,,TOM... ONE LAST THING,I JUST THOUGHT ABOUT THIS,DOES THIS TRUCK HAVE THE DIMMER SWITCH ON THE FLOOR ??? IF SO,, CK THESE WIRES REAL GOOD AND FOLLOW THEM UP TO THE SWITCH..JUST A THOUGHT.