I think the 350SD is probably the best W126 diesel model to have. Its a throwable SWB version with all the nice updated stuff they got in 1989, plus a more powerfull engine. Thats if you can live with the engine, it may fail on you. Otherwise the car itself is great, one of the best.

Look for a 1986-87 300SDL. Same 603 a bit less torque, but they move right along.

__________________
2006 CL500
2009 C300 4matic
1969 280SE
2023 Ram 1500
2007 Tiara 3200