We used a dremel to cut out the 4 squares in the back panel. We have this fan. The two fans on the left were mounted to bring in air. The two fans on the right were mounted in the other direction to pull air out. We purchased this power adapter and this thermal fan controller. The thermal fan controller is set to turns on at 87 degrees and to turn off at 80 degrees so it's not running constantly. I'll try to find time tomorrow to take pictures if there is an interest.

You will also need a Molex Power Supply if you go this route

If you have a PSU from an old PC just laying around like I did, you can run it with a jumper on the 24 pin cable. That's how I'm running 7 Corsair lighting node pros that are running all the exterior to the PC lighting. A jumper can be made with a simple paper clip or a wire and there's ten zillion pics and vids showing which pins to bridge. Or you can buy one premade that bridges the needed pins for you, or a better premade that's ran to a switch. Mine is the latter and that switch is ran to a hole I cut in my desk top so I don't have to reach down there to turn that PSU on and off. A jumper fools the PSU into thinking its successfully got the power signal that normally comes from your PC case to a motherboard. PSU won't turn on without that. (Jumpers were first made so people can test their open loop water coolers for leaks without fully installing it all) If you don't have an extra PSU though I'd normally never recommend a cheap PSU for running a whole PC, for just running something like fans and or lighting you can get PSU for cheap. Like around 40 bucks.

Another option is a AC wall plug to molex adapter like this. Then a molex to the much more widely used today sata. Or you can do a wall plug to sata like this. Which would be better becasue it has an on off on the plug.