Need some suggestions please. I soaked 2 rear heat shield bolts with wd-40 , in order to remove them the next day. One of them came right out the other did not. Last night I drilled out the broken bolt piece in order to use an "easy out". All went well to this point. I then heated the area with a propane torch and quickly cooled it. I then began to work the easy out and snap. Now the hole is filled with hardened steel. Any suggestions?