Maybe I'm not quite understanding you. You mean having your car sitting while you figure out your piping and such? Yes that would burn up some extra man hours, however starting by dropping in a good running 5.2 or 5.9 magnum would gain you a lot of that back if as far as you're going into the engine is to upgrade head gaskets. The beauty of a centrifugal s/c, while more costly, is you could dump in the engine, get it running and driving and add the s/c after the fact, and save a whole lot of man hours in the process.