Use a cutoff wheel on an angle grinder to cut the outer ring off the balancer, leaving the three threaded puller holes attached to the center hub. Then grind the weld flat with the hub, and center drill as close to the middle as possible. The crankshaft snout is 1 1/4" in diameter. Step-drill the hole until it's that big or slightly larger. That will weaken the weld bead so you can use a crowfoot puller to remove the hub. You can probably salvage the crankshaft that way. As mentioned above, the 230 block can become a 250 with a crankshaft swap.
Jerry
