Manual brakes

I'm thinking about swapping over to manual brakes to make more room for the custom headers that will be fabbed, to take more weight off the front of the car, and because I'm not sure if the new engine will even produce enough vacuum for power brakes. I'm just curious as to how a II with manual brakes stops and how the pedal feels. The brakes will be upgraded, and the car will have rear disks and will weigh considerably less than a stock II. Also, do I just swap out the power brakes master cylinder and booster for the manual master cylinder? Do I have to swap out the pedal assembly, too?
 
I was nearly in a four car pileup last night. Have you noticed how fast new cars can stop these days? I wouldn't drive a car on the street without power brakes. Drum brakes are a bit easier to activate without power but discs, forget it.

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