I don't think there's a gain in removing the rear regulators; in fact, I wouldn't remove any weight aft of the B-pillars. In front, on a street car, you can replace items with lighter ones, and also their mounting brackets and fasteners. Delete every part that you don't need. There's a few pounds in the fender splash pans. There's probably a much lighter aluminum heater core for another application that could replace your OEM one.
I agree with the others that (1) that's a pretty car, and (2) it'd be a shame to cut it up in a way that would damage it.