8 cylinder means much heavier engine. Then these things also need changing complete front suspension e.g, shocks coil springs hub assemblies rotors brake system floors of car due to the different routing of exhaust system, ECU, transmission rear differential along with axles, interior will also need stuff as original e500 came only as lhd. My advice don't go for it. Now that you have bought this car if you had asked for advice before purchasing I would have advice to go for e220 as it came with m111 engine which is vtec and more powerful than 230e. But now wish you best of luck. Your car comes out beautiful. Enjoy it