I think you can safely proceed with #5 and #6 the way you are going, just go slowly and try spraying some PB in there as you go working the plug in and out slightly to get it to penetrate...it will carry into it that way.


As for #3 it might just make sense first to try it with a torque wrench and see if you are applying anywhere near what it considered the "safe limit" for them...that torque limit eludes me at the moment but can be found in other posts. I've also posted in the past that I think it is wise to try using an imapct tool on stubborn GPs. There are some low power air or electric tools which would apply the rat-tat-tat impact that I feel would successfully remove them. I bought one recently from harbor freight for $15 which is very compact and has a butterfly control allowing you to easily switch directions. I would bet a beer and a shot that it would remove your #3 in no time.

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz