Search Creality Auxiliary Fan on Amazon if you don't have one and you want one. with the duct, it's the best option for Enders, since the fan speed is adjustable from the fan. Just not with software, unless you are good at that stuff.
The author remixed this model.
I reoriented the part so it's ready to print and tweaked the two cross members so they have a flat bottom and can bridge across. Only need support around the edges of the part now.