Some skillful use of a hand drill works. Start with a small bit, make sure you are in the center of the stud and square. Work up in drill size until just the threads are left in the head. You can use a pick to get those out.
Of course if the drill wanders into the aluminum, you are going to have a larger problem.
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Gordon
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'71 911 Coupe 3,0L
outlawed
#56 PCA Redwood Region, GGR, NASA, Speed SF
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