...the inspiration came that compelled the Founding Fathers to prohibit "Cruel and Unusual Punishment"...
I assume their inspiration was English drawing and quartering.
For a description see Coke's speech in the Gunpowder Plot trial in 1606:
http://www.shakespeare.com/Today/0127.html A traitor...shall...be drawn to the place of execution from his prison, as being not worthy any more to tread upon the face of the earth whereof he was made: also for that he hath been retrograde to nature, therefore is he drawn backward at a horse-tail. And whereas God hath made the head of man the highest and most supreme part, as being his chief grace and ornament, he must be drawn with his head declining downward, and lying so near the ground as may be, being thought unfit to take benefit of the common air...
Or read Catherine Drinker Bowen's excellent biography of Coke, The Lion and the Throne.
Or see Braveheart. Mel Gibson playing William Wallace as a Christ figure.
I've read The Lion and the Throne. An excellent look at Coke, and the life and laws of his time. What a story!