Breaking strut to steering arm bolts on '89 525 w 165k, while trying to r&r struts. Drivers side first bolt off OK, broke second, then heavy use of PB Blaster and two hour soak. Third bolt feels like it is wringing off. This is first time strut removal at 166k.

Passenger side, PB Blaster with short soak then easy off.

Bolt threads have white residue. Is this some kind of locking compound. How treat bolts with factory locking compound to get stub of the broken bolt out?