I have a 1975 firebird. right now it has power steering and power disc brakes. I'm planning on converting both systems over to manual to save weight and drag. Is there any mondifications I need to do to the brakes aside from swapping the master cylinder to a manual disc brake master cylinder? Is there any where to find a manual steering gear at a reasonable price?

Have done this myself on a 71 Corvette--about the same steering and brake systems. Brakes are really simple, as you stated, just change the master cylinder and you might want to install a proportioning valve in the rear brake lines to make fine adjustments. However, the Corvette used an old design power steering, not quite the same as your more "modern" Firebird. Still, the work needed is about the same. Change the steering box and 86 all the power steering components. You might find that the steering arms coming off the front hub are also different (faster ratio) for the power steering and they will have to be changed or the car will steer like a truck, or not...depends on how strong your arms are.

To make the brakes a bit more effective, try a cross drilled front rotor and yes, the rear drum brakes can also be cross drilled and that works really, really, really well! I know of only one person that can cross drill a drum brake properly and that is Nate Jones in Long Beach, Calif.