dumb question, but have you taken the pressure plate off the flywheel? Take the clutch/pressure plate off (they are 10mm 12 pointed bolts if I remember correctly) then once you take those off, there are 6-8 bolts connecting the tranny to the crank which are 17 mm 12 pointed bolts. As everyone has said, you need to put something in the way to stop it from spinning. You can stick a punch in one of the holes ment for the pressure plate bolts to keep it from spinning.