Building an incubator, where do I put the lights and fans

[browning6]

I am building an incubator out of an old mini fridge. My question is where do I put the lights (heatsource) and the fans? I assume spread the lights out and put the fans blowing past the lights. Does anyone know if that is correct. Also I am going to buy the wafer thermostat. Where should it be mounted?

 

[Ridgeline Hens]

Here is the one I built, it works very well. Just right for a dozen eggs.
https://www.backyardchickens.com/a/homemade-incubator-4