Questions about Seats

I just acquired some seats from a wrecked 2002 Mustang GT. The mustang only had 14,400 on the odometer so the seats are pretty much mint condition. I bought both of the front seats (drivers side power), the seat belts, and the parking brake handle for $340. They are "black" which nowadays means more of a "charcoal-like" grayish color. In order to match my interior better, I'm pondering dyeing the seats more of a darker color such as midnight black. Who cares about the heat as long as they look good, right? Does anyone have any experience with dyeing seats and could give me some good tips, or know of any good places to acquire the materials? I did find this site which appears to be a decent site.