If it's a street car, I suggest just leaving the stock brakes on it. Once you start changing things with aftermarket stuff, it becomes more work than it's worth sometimes, especially when it comes to replacing those parts when they are worn. If you really really really want disc brakes, locate some factory or OE replacement parts that can be adapted along with the proper brake booster. That's right! Power brakes is almost a must have with disc brakes.
Everything I stated goes for any normal street car, don't let's the fools on TV and the interwebs and at the cars shows make you think you need to modernize by changing good parts.