A/C Question? After Market System

If you still have all the original ac stuff from the car, that would be way cheaper to put it back. You can buy kits to rebuild it. I don’t think you can just use the heater portion of the box under the dash alone with the ac part (the ac part under the dash) removed. As said above, the heater will still work with the under hood components removed, as long as you leave the vacuum hooked up.