Keezer computer fan

I am finishing up my kegerator today, but I've run into a slight snag. I have made a fan to circulate the air inside the freezer from a computer fan and a cell phone charger. I have an 8" collar. What is the best way to position the fan? It would be easy to simply attach it to the collar, but I'm thinking that hanging it a couple inches in the center of the lid would be the most efficient (like a ceiling fan).

I'm not exactly sure the best way to attach it to the lid. Maybe use some of those adhesive wall hangers?

Any thoughts?

NM, attached to the collar for now.

Lowes. A few plastic spacers, long sheet metal screws.

Mine is screwed to the center of the lid, about an inch off the plastic.

I have three. Basically I screwed a piece of wood about 1x8 into the lid, using some drywall anchors to give it some stability. Then, I screwed the fans into the wood. That way, they are spaced about an inch below the lid, and point down into keezer.