[lineslinger]

Job from Hell, although mine was an iron block, you will learn new words removing the old ones and your neighbors will send their children to their rooms with their door closed.
I flattened the teeth on two sets of vice grips, as recommended by Xracer I ground the edges flat, then rounded them off trying to turn them. I tried driving them out from behind after heating the surrounding area, bent the punch. I tried Brents idea of the slide hammer, wouldn't budge.
I finally said &%$k it and drilled them out using progressively larger bits after each pass.

I did use Robb MC offsets and they worked quite well.