Going on a diet

The waterpumps on our early cars have the water outlet on the opposite side from the later ones. Does anybody make a direct replacement aluminum pump that will work on our early 273's?
If anyody has their car apart, can you tell me how much the side glass and regulators weigh? Thinking about lexan on the door windows and quarter winows as well as eliminating the regulators if there is enough weight savings.
I have a regulator here for the door and it was 3lbs 14oz. The vent window was 1lb 4oz. Door glass 9lbs 12oz. Sorry the back side glass I can't find.Jysnflem