Warren is right. Those plug pliers are critical to keep from pulling the ends off the wire. They will save your hands too. I did it by hand for years (not on Mercedes), but when I bought the SL I decided I needed it and it makes all the difference in the world. I bought one that can be set straight or two angles to the right and left making it 5 positions. Money well spent.

Oh yeah, you want to twist the boot first and twist and pull if they won't come off. Do not bend to the side or you will break off the insulator.

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Steve
1985 Mercedes 500SL Euro (Gray market)
1995 BMW 520i Euro (Gray market)
1992 BMW 525it Wagon
1994 Honda Del Sol Si