I 3d printer a fan cowl with an area for holding liquids. This is used with an ultrasonic atomizer to vaporize water or other liquids to flow through the heater core.
The actual electronics consist of the PID controller, power switch, 5v/12v power supply. Speed control for the fan and a button to activate the ultrasonic mister.
I re-used the same svg from my "Mr Pickles" project for the case. I added a few holes for the power, switch, PID Controller and more for the power connections on top.