Its a normal bolt, and yes the engien does reciprocate the "wrong" way so no starting the engine to torque it. just use a big breaker bar with a long pipe and lock up the pulley somehow. i've seen it locked up by useing a chain type strap wrench, theres also a specific tool that will lock into the pulley , also you can use on of the holes on the pulley and the edge of the socket and a suspension arm as three points to lock it using something like another ratchet. cant explain it any better than that. its tough. most impact guns cant do it.