Putting the car on a diet
Have you replaced the starter motor with a light weight mini starter (saves over 5 pounds, starts quicker, less power draw)
Since you are doing light weight disk calipers, what about using a newer aluminum MC (those old dual bowl cast iron Master Cylinders are so heavy)
Also, if you go with aluminum brackets with a fiberglass or aluminum bumper, might as well go with the aluminum bolts... Just saying :D
Good luck... sounds like a "fun" project!!!