I have a 1969 Imp with factory AC which I want to remove. In order to disconnect it, I believe I have to evacuate the system, what is involved with doing this safely? What are the complications in doing this, does it affect the heater as well - I have a feeling that it is not as simple as just removing the components under the hood and replacing it with an AC delete plate. I need the heat, but not the AC and it seems like modifying everything for new refrigerant is more of a pain than it is worth. Any help is appreciated.