the v6 would be very easy in terms of electronics and fitting since no parts will need to be replaced like exhaust manifold or other minor parts like radiator fan. The main issue would be the ECU and you could spend some good money to get it taken care of. i would rather put that money for ecu into the suspension or something and still end up with about the same power and less weight. Their is many pro's and con's V8 would mean you would never need a bigger motor lol or lets hope. we could use the v8 with a blower til it blows lol and then forge it and crank up that boost. Any v8 AMG that come forged for our applications.