I am going to be adding the full set of front and rear Porsche Cayenne brakes, using the kit linked and Dodge Viper rear parking calipers... and I am just missing the rotors now. Before installation, just need to sandblast and paint the calipers the proper shade of red.
Definitely looking forward to much better brakes before I go to the track. Though I wish I could do a lap of the 'Ring like you Europeans get to do 
Are you changing the master cylinder?
Most conversions I've driven using Cayenne callipers have little braking feel due to the miss-match with MS size...you push the pedal too far and end up with no feel.
Why fit such big rear callipers when they only do 10-20% of the work?
