1 and 2 really depend on your budget, skills and goals. Turbo is the best upgrade for power but I would not go that unless 700 or more horsepower is the goal.

3. Nobody can answer this without knowing your goals and rear tire size and gearing of your Tremec 5 speed. I would recommend an 8 3/4 or Dana 60.

4. You mention Pro Touring. Then discs are a must. Drum are for stock type restorations with no desire to improve braking.

5. FI Tech is definately an upgrade from a carburetor but it is the bottom of the barrel for fuel injection. Consider something that will control fuel and ignition.