Well, I've not done it on a 123, but on a 124, there is a connection from the pump under the hood which has to be disconnected first. Then the nozzle itself sort of works its way out with some twisting and pulling. The rubber base/grommet gives it a bit of play.

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1994 E500 199/Gray 82k
84 300D (Salty) Orient Red/Palomino 141k
88 300CE (Ersatzhammer) 904/Java 163k -- Turbo Technics twin turbo kit, AMG Gen I body kit, Sportline steering box and steering wheel, Sportline/Eibach /Bilstein Sport/500E suspension, Quaife LSD in 210 mm diff case, Silver Arrow brakes.
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