doesnt it damage the belt grooves in the pulley ??

 

A chain wrench? Damn. They make a tool that bolts up where your starter goes. It engages with the flywheel and locks the motor up. The balancer is not keyed and it's held on by a right hand thread. If you don't get it tight it will spit the bolt out. I think GM calls for 37 ft lbs and 120 degrees after that.