FOUND PTO CLUTCHES FOR 6800 YAMAHA. STENS 255-507 ELECTRIC PTO CLUTCH/OGURA MA-GT-EXM3XS. I FOUND THEM FROM OREGON POWER EQUIPMENT,SALEM,OREGON $235.00 FREE SHIPPING. I ORDERED SATURDAY AFTERNOON AND THE MAILMAN HANDED IT TO ME MONDAY AFTERNOON. IT HAS A 1INCH BORE AND THREE INCH OVERALL HEIGHT (PERFECT). THE ELECTRICAL CONNECTOR WILL HAVE TO BE CHANGES. THE PULLEY OR SHEAVE IS SIX INCHES INSTEAD OF 5AND A QUARTER. A GOODYEAR B68 BELT(1 INCH BIGGER) WILL COMPENSATE. YOU'LL HAVE TO ADJUST THE SPRING TENSION ON THE MOWER DECK. THE BLADES WILL TURN A LITTLE FASTER. MINE IS WORKING FINE! I RECOMMEND CUTTING OFF THE CONNECTOR FROM THE OLD PTO AND SOLDERING IT ON THE NEW ONE....CHECK YOUR POLARITIY. GOOD LUCK