Was installing dp at my friends shop and we got to the last stud holding the stock dp on the turbo and it seized up part way out and rounded the hell out of the head. We tried for an hour to get the damn thing off but can't get anything back there to grip. We had to leave when the shop closed and I'll be back there tomorrow after work with a new set of Bolt-Grips to try and a dremel with a cutting wheel. If nothing else it may be small enough to fit, cut the bolt off, remove the stock dp and have some thread exposed to use a stud extractor or something on.

Any other ideas out there?

Did you leave the bolt well-soaked in a penetrating oil overnight?

For a couple nights now ... Been there since Saturday

Did you try a torch?

You may just have to replace the stud all together (if it isn't stuck as well)

Ended up breaking off the head of the stud when we tried again today. Had to drill it out. Which was awesome. It was obvious the turbo has been replaced before, missing a stud on the stock downpipe and a couple stud were cross threaded. Ended up re tapping all the holes. Damned if the tap broke off in the last hole. Couldn't get it out and hardened steel is shit to drill. We slapped the new dp on with 4 bolts. What a pain in the ###. I'd say this would not have been too bad had every bolt not been seized! Damn this was a pita. Never taking that thing off.

Didn't get to drive but a few seconds to make sure it would turn on and no exhaust leaks. Felt like it was gonna pull hard. Pretty happy with that, but nothing about this install was easy or went well. Mazda gave me no love on this one .