If you want to do something unusual, I've designed bracketry to adapt C5 Vette rotors and 4-piston Dodge Viper (brembo) calipers to the front of my M-II spindled cobra.
You end up with 13" rotors that are easily replaced for $60-80 a throw, and a 4-piston caliper that is bomb proof.
I also designed bracketry for the 9" small bearing rear in my car to use the same rotors and calipers. I have 4-piston viper calipers and 13" vette rotors on all 4. I can rotate pads and rotors.
I had these parts cut from 316 stainless on a CNC mill; but you could just as easily have them laser cut or waterjet cut from plate for far less.
http://www.racesystems.com/cobra/bracket.jpg
http://www.racesystems.com/cobra/complete.jpg
I'm running a chevy bolt pattern (5x4.75) so I didn't have to redrill the rotors, but you could easily do that.
The hubs I'm using are billet aluminum hot-rod stuff; about $200 a pair. They come drilled for both chevy and ford pattern and accept all standard m2 bearings and all.
Of course, this all started because I ended up with free Viper calipers from a friend. However, I've seen these calipers go on ebay for a song; so it may be something to think about. I don't think I've ever seen more brake on a MII spindle.
Byron