To give credit where due, I attempted (and succeeded) with this due to watching this Welding Tips and Tricks Video:
http://www.weldingtipsandtricks.com/...oken-bolt.html

I've got a 67 Cutlass Supreme Convertible and am spiffing up the engine compartment. I decided to take off the steering box. It's bolted to the frame with 3 bolts. 2 bolts came out whole and 1 didn't.

Starting Point:
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After removal.
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There's the 3 bolts - 1 good, 1 partially rusted and one in pieces.
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What's left in the steering box.
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Putting on a nut with a washer to weld to the bolt.
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Putting a nut on the other side in hopes that I could put a wrench on both sides.
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After nuts are welded on both sides.
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One snapped off.
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Weld another nut on.
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Yay, the nut on the left is turning!
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