Hey guys, I have an 07 diesel sport, and the back parcel shelf speakers sound pants, very dull and muffled as if they are covered up. I don't have sat nav. I'm thinking of doing a speaker upgrade with no mods or as little as poss. What are the best type that will fit straight in? - - - Updated - - - ?Anyone? I am also not sure if it has an amp or if the amp is built into the standard head unit. I don't want anything to classy just something with a bit more guts. Is it true the premium pioneer speakers will drop straight in?