There was someone that "put" a late model ( 600hp ? ) twin turbo V8 driveline " in " a old 190 SL body. What they really did was hang 190 body panels on the later chassis so that really does not count as a motor swap.

If you are going to make a swap, later electronics are so integrated that a complete wiring vehicle harness / instrument cluster swap would likely prove more fruitful that trying to mix wiring.