A few years back, a thermostat housing stud broke off FLUSH with the aluminum cylinder head on my Datsun. No problem, I thought, here's a chance to use my new Easy-Outs. I drilled a nice hole through the center of the broken stud, inserted the easy out, proceeded to turn the easy-out and... snap, I broke the *%#@!# easy-out off. Having exceeded my mechanical capabilities, I consulted a friend was a mechanic for many years working on all sorts of machinery and equipment. He said "No problem, take off the head and bring it to the shop", which I did. My friend then filled a wash basin with water and put the head in the water with the area of the head containing the broken stud above the water line. He layed a nut on top of, and centered on, the broken stud and then quickly arc welded the nut to the stud from the INSIDE of the nut. Then, a wrench was put to nut and the stud came out easily. I was amazed.