well I have an slk r170 '99 and the sump on it has four bolts, the thing was too rotten to see if the rear 2 bolts were in recesses, 10 mm I recall so not a major job to get off, have some stands under it to support it as it will drop as you start to loosen the bolts, but don't ram it tight in, leave a little room so you can get it out when all the bolts are out, one more thing! on mine there was an air scope under the intake side so you need to drop it about 4 or 5 inches before sliding it forward.
it may be completely irrelevant to your model, however, it is still a sump guard, can't be too dis similar
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