There isn’t an adapter made for mating the 617 to a ranger trans yet. The fuel system will be easy, just pull the fuel pump off, adda hose and a sock to fit in the original spot. The wiring would probably be a bear. You’d have to remove the whole engine harness and ecm, locate and remove the wiring for the sensors that you’ll be retaining, the ignition wiring, charging system and splice them into the Mercedes engine harness.
The engine mounts will need to be fabricated, electric fan probably installed, exhaust fabricated or done at a shop. A 4.0 radiator should be sufficient.
You might check with Doomsday Diesel, to see if he’s developed one for a ranger based trans.