The best way to get broken stud out that I have found is to use a dotco 90* 1/8" angle grinder, this tool is real small and gets in tight places . I call it my dentist drill. Then use 1/8" 4 flute carbide mill bits.
I bought the stuff off ebay, the grinder is a little pricey but worth every penny. I bought a lot of 50 bits, it usually take one bit per broken stud. I have done MANY Ford trucks with this tool, Its the best way I have found so far. Still sucks tho, but you can make good $$$. Oh, I'd recommend using only Ford studs, nuts and gaskets also.