I installed this unit from Restomod Air: Vapir II ... and used this controller, but in black: Reactor - single-knob-a-c-control .
The unit is smaller than the OEM heater core/evaporator box in every dimension but length, so you have to be careful with its horizontal position. That being said, I mounted it approximately where the OEM unit sits. I even used the OEM mounts with an adapter bracket. Restomod Air now makes an even smaller unit: Bantam II which should be even easier to install. They even have a Bluetooth option that lets you use a smart phone or tablet as the controller (although I'm not sure why anyone would want to do that!).