I have many 3.0L turbos, and they are interchangeable with 3.5L's in W126's, but not in W140's. I have one I'd like to swap out if anyone has one with a known good seal. This one works fine, and feels pretty tight, but is passing black oil stains through the crossover. Is seal replacement pretty easy? What would it cost for a rebuild of my turbo assuming if cant readily find one?

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1987 300SDL #1, 1987 300SDL #2, 1980 240D, 1982 300SD, 1994 S350, 1990 350SDL, 1991 350SD, 1985 300D, 2005 E320CDI

Gone, but not forgotten: 1981 300SD, 1982 300SD, 1987 300SDL, 1983 300TD, 1980 300CD, 1981 300SD #2, 1987 300D, 1987 300TDT, 1980 300D