I'm considering buying a W140 s350 with a bad 3.5L. I've swapped many 3.0L's into 90 and 91 W126's that had 3.5L's. But never attempted a 3.0L swap into a W140. Are there other considerations that are unique that would cause issues? In other words, are there bolt-on accessories on a W140 3.5L that do not exist on a W126 3.5L? Are there those types of differences that would produce any unique challenges fitting a 3.0L into a W140 that wouldnt exist in a W126? I understand the major differences in complexities with electronics, and non-engine related chassis designs, but speaking engine to engine, are there W140 centric areas of concerns with this swap?

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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