if im not mistaken there should be two grey plastic "ears" on the rear of the headlight unit, squeeze them and it should open downwards, then you just unclip
and unplug the old bulb and put the new one in, my description may not be exact as its been a while and the car isnt here right now, but its pretty simple, just look on the rear plastic part of the headlight unit, and be gentle as most of that old plastic maybe a little brittle. good luck!

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E30 B25
126.036
123.130 with 616-Frankenbenz (sold)
124.030-Greyhound (sold)
124.030-Schnauzer (sold)

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