Any tips on how to get this out? This bolt was sooo stubborn, even with PB Blaster, that this stupid thing stripped with my flex wrench.

 

Get a 6 point box wrench on it, then once you have it broke loose then go back to the flex wrench.

 

If that don’t work. Use steps in order.

0) if you can weld weld a nut on it.

1) use an extraction socket. They grip into the bolt.

https://www.lowes.com/pd/IRWIN-BOLT-...B&gclsrc=aw.ds
2) drill out the center and use the largest bolt extractor you can fit. Be careful if you crank them too much they can snap off in tje bolt and make it even a harder job. I would use one and crank it slowly and if you feel like it’s going to sheer stop and go to step 3.

3) drill out the bolt. Go small to larger bits going slow and use oil. When you get to tje theeads use a pick to get tje bolt pieces out then run a thread chaser through it.

4) drill it kit completely including the threads. Insert a helocoil kit.