Lee:
It can be done, but is complicated by the fact that the bolt bottoms out in the frame; and it’s a fine thread deal which seems to make it worse.
First, this is an important part of the truck and an expensive one to boot. I would remove the windshield assembly from the truck and rest it securely on padded saw horses. Next, soak the thing for a day or so with a good penetrant/ like Gibbs.
Next, file or carefully grind the remaining bolt section so it is flat. Center punch it very carefully. Get a GOOD set of reverse drill bits. Start with a small one and work up. Mark them with tape so you don’t get into the frame. If you’re lucky, it will give up and come out with the drill bit. Heat is your friend here. But the proximity to glass means no torch!
If it doesn’t come out, you need a blind end tap, so you can cut new threads.
Good luck.
