If you've not used ball bearings, can you not just try removing the putty and undoing the bolts? Failing that, new HSS metal bit (or a few) about the size of the holes and drill out the bolts.
I thought the anchor bolt expansion casings would have made that impossible but i will give it a go.
@dubkev started
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If you've not used ball bearings, can you not just try removing the putty and undoing the bolts? Failing that, new HSS metal bit (or a few) about the size of the holes and drill out the bolts.