You can switch it over to non A/C. Believe it or not the non A/C box will cover the hole 95 %. If it doesn't weld a small plate to cover it at the top. That way you will have a blower, heat and defrost etc. If it's just a race car and you don't need those things just find a non A/C box. You will also have some wiring to do from A/C to non A/C heater control if you want that to work. It's a cheap way to go and looks factory.