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I'd be careful using a jawed puller because you can ruin the balancer.
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At this point, if the balancer will come off with a puller or something, I say screw the balancer. Get it off of there and replace it. Of course, if the bolt broke tightening it, it will probably come out easy. But it doesn't sound like thats the case here.
They fail with age, and I don't think a replacement goes for much over $60. The time and effort spent trying to get this one out without hurting it MAY exceed that cost, if his time is worth much to him.
Just my opinion though.