I agree brakes are something you should not have to upgrade for solo 2. Hawk brake pads are great we've been using them on the race cars for years, but they take alittle heat in them to start doing their job and can be a bit noiseier than most street guys like.
The big brake package you read about in CMS, that Carl H. did on the Modern Midget used the SCCA big brake set up, all SCCA raod racing Spridgets are allowed this mod, I've used it for decades on my F-production race cars, it''s a Spitfire rotor, MGB caliper, with a special adapter that goes in between the Spridget hub and the Spitfire rotor. I wouldn't recommnd except for all-out racing, it's one PITA to get on the car and get everything aligned up, most of the times you have to do some machining to the MGB caliper mounting ears, somethime even to the rotors themself, so you better have a mill and lathe at your use to do this if you want to get it right. I installed maybe a dozen of these on race cars over the years, and I would never endorse it for the street, but if you're brave, you can get the special hub/rotor adapter from Winners Circle.