Stuck bolts

I would tend to agree with the actual arrangement like this. Try putting two nuts in a vice with one ontop of the other and try screwing a bolt through them. This is what it would be like trying to screw through two threaded plates.

If there are nuts on the bottom of the bolts there must be a way to reach then with the whole lot in place.

The Impact Wrench I had in mind was not part of an Electric Drill, as seen here http://upload.wikimedia.org/wikipedia/en/4/40/ImpactDriverWithBits.png
the hammer action of most drilling machines is for drilling masonry and concrete not tightening or loosening stuck nuts and bolts.

It is good that you got it to bits in the end and obviously learnt a few things along the way.

What is your next project we can assist with?