Reply to "water temp sending unit"

THANKS! I STAND CORRECTED! A FEMALE SQUARE HOLE! I RAN INTO ONE A FEW DECADES BACK ON AN OIL PASSAGE OF A PONTIAC 400 (IT WAS 5/16" SQUARE, NO SUCH DRIVER!). SO I TOOK THE NEXT SIZE LARGER SQUARE DRIVE (3/8") EXTENSION AND GROUND IT DOWN, (OFCORSE YOU NEED A GRINDER) SO I HAD TO HAMMER THE VERY, VERY SLIGHTLY TAPERED SQUARE SHANK INTO THE FEMALE HOLE, LOCKING IT INTO PLACE! AND WITH ZERO PLAY. THEN USING AN ADAPTER TO A 1/2" BREAKER BAR APROX. 20" LONG I GAVE IT A GRUNT, SUCCESS!! SHE CAME LOOSE! TRY IT, BY MAKING IT SO TIGHT THAT YOU HAVE TO DRIVE IT IN, MAKES IT LESS LIKELY TO ROUND OUT THE SIDES. AGAIN, GOOD-LUCK, MARLIN.