1990 Ford Ranger

WHEN VEHICLE IS EITHER STATIONARY OR IN MOTION THE PASSENGER HEAD LAMP MELTS, SOMETHING IS CAUSING THAT ONE LIGHT TO OVER HEAT AND HAS MELTED THE ENTIRE HEAD UNIT. I HAVE VERY LITTLE VISIBILITY WITH HEAD LAMPS ON. BATTERY IS CONSTANTLY CORRODED, NO MATTET HOW MUCH I CLEAN IT. AC/DEFROST DOES NOT WORK. RIGHT BLINKER DOES NOT STAY ON, SHUTS OFF WITH THE SLIGHTEST MOVEMENT OF STEERING WHEEL. GAUGES DO NOT FUNCTION PROPERLY NOR DO THE LIGHT INDICATORS. CHECK ENGINE LINE COMES ON AFTER EXCEEDING 30MPH AND WHEN I HAVE IT CHECKED IT'S ONLY THE O2 SENSOR. TRUCK GETS HOT BUT DOES NOT OVER HEAT AND ALL FLUIDS ARE TOPPED OFF. WHEN IN MOTION I CAN SMELL THE EXHAUST AND CAN FEEL THE HEAT FROM THE ENGINE COMING THROUGH THE GEAR SHIFT MANIFOLD. AT TIMES DOES NOT WANT TO SHIFT IN REVERSE. PASSENGER SIDE DOOR DOES NOT SHUT PROPERLY, I BELIEVE IT WAS WRECKED AND THE DOOR WAS POINT OF IMPACT. I BOUGHT THE TRUCK FROM PREVIOUS OWNER FOR $1,100 AND HE WAS UNABLE TO TELL ME ANYTHING REGARDING THE VEHICLE EXCEPT THAT IT DIDNT HAVE A SPARE OR OWNER MANUAL. MY FUEL IS LEAKING AND I CAN'T SEEM TO FIND THE POINT OF ESCAPE. I'VE ALREADY HAD TO REPLACE THE STARTER AND SOLENOID TWICE BECAUSE IT WOULD NOT START. AFTER REPLACING THOSE ITEMS IT STILL WOULDN'T START UNTIL I HAD PULLED BY A U-HAUL AND I HAD TO POP THE CLUTCH TO GET IT TO START. I HAVE BOUGHT OVER 6 HEAD LAMPS IN TWO WEEKS ALONE. I WORK AT NIGHT AND IM CONSTANTLY GETTING PULLED OVER; SO I EXPLAIN TO THE OFFICERS WHAT'S HAPPENING. I HAVE HAD THE TRUCK SINCE FEBRUARY AND DIDNT KNOW WHAT TO DO UNTIL I TALKED TO A MECHANIC. THE TAILGATE DOES NOT OPEN AND I HAD TO TIE MY MUFFLER UP BECAUSE IT CAME DETACHED FROM THE FRAME AND DRAGS THE GROUND. I CAN'T AFFORD TO BUY ANOTHER VEHICLE AND I DONT KNOW WHAT TO DO.