First of all thanks for the reply. I find this site to be much better at people actually replying to posts compared to others...
So you are suggesting leave the cylinder head on and use a reverse drill bit to try and remove the bolt.
Not clear on the tubing point. You mean find some piece of tubing small enough in diameter to fit in the hole in the cylinder head, yet large enough to allow my drill bit in right? Copper tubing or what exactly would I be looking for?
Maybe the reverse drill bit docs will say or I can do some research but what is the size I would look for in relation to the bolt? 3/4's the size of the bolt to be extracted?