You have 2 GP stuck that you cannot get out? Have you try blow torch them or use penetration oil?

Can you get a socket to them or they are completely rounded? If they are rounded then it is no different from extracting a bolt. I would do a search on the data base to see how they can be extracted. May be you need to drill a hole and use an extraction bit. If the worst come to the worst then pulling the head may be the only way out.

Good luck.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

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