How much weight can you shave off of an A-Body...and still have it look/drive like an A-Body?

I admit I am NO racers, but in SE Texas we don't need a heater, so out goes the box, I will remove AC as I hate the clutter. If its too hot to drive the classics, I drive the modern daily! If I omit the back seat, it saves that upholstery bill!!
OK so I am cheap and squirrely!!