Air-compressor off, drilled the crap out of the bolt, then pulled the compressor towards me and it snapped off at the head - proves when all else fails get angry.
The correct powersteering belt is now on (Gates - 4PK925), First belt I've changed on my car myself, it's nice and firm - but not too firm ;)
What's next - brake lines, horn install, battery tie-down, alarm, horn and swap the steering wheel back to the stock one.
Wish list - coil-overs & complete suspension overhaul.
EDIT - Photo/Vids coming soon.