Originally Posted by Donald
They sell extractors that look like a socket with teeth. I got a set that are Craftsman. But you may not have enough room on the upper side.
Get some cheap Torx bits and pound in the largest one you can get to fit.
I assume this was allen or Torx to start? Did you first get in there with a pick and compressed air to blow out the dirt so the proper allen or Torx would fit. Or used one too small thinking it was right?
I would heat with a propane torch and cool a few times with PB Blaster.
Maybe a smack or two with a hammer to break the rust.
I would not advise drilling a hole and trying to use a screw extractor. The last thing you want is a screw extractor snapped off as part of the mess.
It was allen to start and I had the proper socket adapter. Let's not get into how it got f'd up. I put a good amount of torque on it with a cheater bar and the top one broke off with a loud CRACK. The bottom also made a loud crack and I knew it was 50/50 rounded out or broke loose, but wasn't as lucky on that one.
I chalk it up to experience and trying to graduate from 2 wrench out of 5 to 3 wrench out of 5 skill set.