One very simple solution is to do a little machining on a 2-groove balancer for a 250 inline six to make the pulley grooves line up correctly. I'm not too impressed by that process, as the rubber isolator between the two parts of the balancer carries the torque load of pulling the belts. My method uses a 6" diameter balancer for a 283 V8 and a 2-groove pulley for a big block V8 is installed backwards to its normal position. Some very basic machining is done to the balancer hub, same as the 250 gets. With that setup the balancer ring is free to move independently, and the pulley is driven by the 3 bolts that would usually be used to attach a puller.
Jerry
