Thanks for all the input! I've decided to go with the 5 pin wheels with adapters. I think this Wilwood kit will upgrade the brakes nicely.
Wilwood High Performance Disc Brakes - Front Brake Kit Product Number: 140-10738-D
There's some modifications needed to the spindles to make them work but it looks fairly straight forward. That will give me plenty of front brakes and I'll see about getting vented rotors for the back, helping with the cooling.
Nobody has chimed in about the exhaust question. Maybe I'll start a separate thread regarding the exhaust in a few days. I think I put in too many topics in one thread.
Thanks again.
Kim