I just did that with my '79 300D diesel. The toughest part was lining up the old engine mount holes with the frame holes from underneath the car. Once aligned, a good quality rounded allen head wrench (8mm and 6mm)came in handy. Had to jack up the engine 2" to get them out. I used a piece of wood laying flat under the oilpan right next to the flywheel to apply the hydraulic jack. Be very careful setting the jack. You don't want anything to slip out when you have your hands in there!