I have this whole setup in my car. Aerospace mc and 4 piston calipers on all 4 corners. Once you redrill the pedal assembly to move the pivot point there is really no big deal with pedal effort what so ever. I don't think I would ever have another fox with power brakes. Granted on the last trip to the track the wall stopped the car far faster than the brakes ever could. I would not recommend using the wall to stop; however.
That's the key. Redrilling the pedal to change the geometry.
With regards to the OP. Was this done? If so, this will need to be changed back to original geometry if you decide to change to power brakes.