I was on Ford.com and was just playing around building a Mustang. I got to the audio section and it the Mustang comes standard with the Mach 460 stereo, right? Well, I noticed an option for a "Mach 1000", what the hell is a "Mach 1000"? What is the difference in the two stereo systems? The numbers after the word "Mach" does not denote wattage, right? How would one go about upgrading to the "Mach 1000"? Is there even a difference? Thanks in advance!!