There are some USB radios out there all with different degrees of quality. There are several threads about these solutions and there's another group building a decent one -- I haven't checked in on those guys in a while so I am not sure of the thread. Here's a ready made one from
Griffin
You could probably use your head unit and line in on the laptop. I am using the XM Direct and cable -- I never listen to FM anymore...
But there are other options and products for radio. Good luck on your project! Glad to see more Mustangs getting into the mix!
- Jeff
Edit: Here's the thread with the HU Quality USB/Serial radio :
http://www.mp3car.com/vbulletin/show...t=serial+radio