I currently have a 79 300D that the engine is slowly dying, currently consuming a quart of engine oil per 100 miles. I had the engine apart awhile ago to replace the crank and bearings from another engine that had other problems, I knew the sleeves were badly worn then, they really must be now....anyways, I came across a 73 450SEL that runs but the body is badly rotted, I was wondering if it is possible to squeeze the V8 into the 123 car without serious modification, and would I need the rest of the drivetrain as well. I know I will have to change the fuel system as well as the exhuast system. The other car is whole, so parts are all there.