Why do you need to switch the oil pans?
You'd need the rod and linkage off a 116 which controls the transmission like your existing rods, except following a different route down to the transmission. I'm not sure the engine compartment of a 123 has enough space for the rod to follow the same route as it does in the 116. does anyone know for sure if it will fit?

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13