I went to a stereo shop and told him I did not want entry-level but I also did not want top of the line. The quote below is to replace the two front tweeters and speakers but not the rear and to add a custom-built Box for a 10 inch woofer to go in the passenger side behind the rear wheel (Looks like he left the tweeters off of the quote).
The speakers are available for $1500. The audio control processor is an analog model, digital model gives better sound tuning options and starts at $600 up to about $1500, he said if I went digital it would take them about four hours to fine-tune it and give me three sound options for the type of music I am listening to (rock,rap etc.)
For you ML owners,he said that is the best stock system out there.
Side note, I just installed iOS8.0 on my iPad Air and could not upload the picture