rear wheels to clear the stock brakes? :) those are weld draglites correct?
also what do you plan on doing to the rear suspension? maybe backhalf or mini tub it with a solid axle? i doubt the irs is gonna be able to hook up that much power......thats an awesome project you have going. i have a parts car ive stripped to the frame, and im about to cut the whole rear end out of it for a backhalf :)