Its ur lucky day. This is a brand new MAC system on a car(video taken 3 years ago). It sounds even better now that its been on the car for about 3 years.
have you been to mustangexhaust .com
if you haven't go there and register. they have different systems for 5.0 3.8 and 4.6 engines with headers x or h pipes and different mufflers or stock headers and h pipes too. it is a nice place but don't ask how to make it sound like a v8 or you will get flamed. i have gotten it close enough to make it like a v8 but they say it cannot be done