Yes
Haha, yes indeed. And I do have a fan. It's a smaller cooler---> bulb is right under the handle part. fan is where the cords stick out. Thermostat is in the mailDepends on if you have a fan. With a fan, it won't matter as much depending on where everything is situated. Without a fan, a light in the center will create cool zones in the corners. I'd put the wafer and your most accurate thermometer closest to the center mass of the eggs.
Always give eggs the sniff test before putting into your clean incubator.