Personally, l wouldn't get a torch of any kind near it except as a last resort. The whole mother is aluminum, and aluminum warps very easily. The first thing to do is mark the broken off stud with a center punch, before you ever start drilling. You may wish to very carefully smooth the surface with a dremel first to make that easier, use extreme caution not to damage the head if you do. Once you have the punch centered and started, make sure the mark is deep enough that your drill doesn't wander. Use a small drill, it will be easier to hold steady, and when drilling in steel low rpms are better. TapMagic or similar cutting fluid will help to keep the heat down and your bit sharp. The stud is small enough you should only have to use the drill bit specified for the extractor you are using. Most auto parts stores carry extractors, as well as home improvement stores if you don't want to wait for Amazon. When you do start turning the extractor, gently tap it in first with a brass hammer, the use slow and steady pressure - carbide is very hard - and brittle. Impact is a sure way to break one off in the stud, and the. You're really screwed.
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