The six extension bolts are loosened with a 7/16” wrench. Be certain to place another open-end 7/16” wrench behind the pulley, to hold the head of each of the six bolts while loosening and removing the retaining nuts. Leave the six bolts in place.
Note: Access to each bolt is facilitated by using a 1-1/16” box wrench or socket, rotating the crankshaft bolt as needed to gain access.