I think finding a good 3.5 motor is the only issue. I think I recall Someone swapping a 3.0 into a 350sdl w126 for a straight swap. I don’t know if that would be more work for the notable downgrade on a w140. There might be better motors to install but that complicates things. So it’s priced to get the attention IMO. Finding the taker for the project might be harder. You can always offer for your wife to try and handle the sale.

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Past mb: '73 450sl, '81 280slc stick, '71 250, '72 250c, '70 250c, '79 280sl, '73 450sl, parted: '75 240d stick, '69 280s, '73 450slc, '72 450sl,