Yea that is the dipstick tube under that cap. You have to remove the clip through it. Like this Red one. Pull it out or break it out whichever. You don't need it.

Looks like this



Credits for Photo's to Oberoi from Sidney Australia over at the Benzworld.org

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1983 300D-Turbo - Deep Blue w Palomino MB Tex (total loss in fire 1/5/09 RIP)
1995 E320 W124 Polar White/Grey Mushroom MB Tex
2005 F150 Supercrew - Arizona Beige - Lear topper
1985 Piaggio Vespa T5 - Black and Chrome

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