I made a tool that holds the balancer stationary so the large bolt can be removed and then tightened with the crankshaft turning. It consists of a round steel piece that fits on the balancer after the pully is removed. The holes in the round piece line up with holes on the balancer. It looks like a large washer. There is a piece of pipe welded to the round piece that goes down and hooks under the crossmember beneath the engine. Once in place it works slick. I have used this several times on my '67 Fury with 318 engine.
John