I am not a master but both cars are unibody, the body's are the frame. There is a front subframe but it would be easier to adapt the motor and trans to the existing body/frame. The rear end designs are quite different so to fit the newer rear would require designing and fabricating mounts.

__________________
1968 230 W110 +3.5 M116 & 4-Speed Manual
1985 300TDT S123
1985 500SEC C126