98 E320 4Matic Wagon 100K miles...

I (and my indy mechanic) have been chasing oil leaks. There is an engine oil leak from the left (driver's side) front of the engine. Oil runs down and drips off the left front corner of the oil pan when the car is at rest. And the trans pan is leaking. So far we seem to be throwing parts at it. Replaced so far:
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O-rings behind the oil filter housing where it attaches to the timing chain cover near the oil pressure sending unit.

Oil filter cap.

Transmission pan gasket.
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I am stumped about the engine oil leak and am tired of throwing part$ at it. My question: is this a common leak "area" and what part commonly leaks from this corner of the engine?

My indy mechanic says about the continued trans pan leak: the pan itself could be warped and we might need to replace the entire pan. I'm no MB expert but a warped pan seems a little far fetched to me. The mech says he's seen it before but I'm beginning to think he botched the gasket replacement... Or maybe never did it in the first place...

Any suggestions from this gallery? Thanks
-Mike

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1998 E320 4-Matic Wagon