Dave, congrats on the SDL.
It sounds like a sweet machine.
I love my SD, a one owner '84 that the PO had traded at a Ford dealership.
I doubt that I have more than $10-11K invested in the car in the past 5 years.
Murphy's Oil Soap?
I use that on my kitchen cabinets and wood furniture at home, but I've never heard of using it on leather.
Even MB wood is lacquered to the point that it should probably be treated more like a plastic or paint than wood...
I've used Lexol Vinylex on my dash, with amazing results.
Neither of my MB's have leather, but I'm told that Leatherique is the best stuff to use on leather.

__________________
Bob Roe
Lehigh Valley PA USA
1973 Olds 88, 1972 MB 280SE, 1978 Datsun 280Z, 1971 Ford T-Bird, 1972 Olds 88, 1983 Nissan Sentra, 1985 Sentra, 1973 230.6, 1990 Acura Integra, 1991 Volvo 940GLE wagon, 1983 300SD, 1984 300SD, 1995 Subaru Legacy L wagon, 2002 Mountaineer, 1991 300TE wagon, 2008 Murano, 2007 R320CDI 4Matic 52K, some Hyundai, 2008 BMW 535xi wagon, all gone... currently
2007 Honda Odyssey Touring, 2014 E350 4matic