Thanks for the info. I hope your 'bator goes well, I plan on building one too, but I'm starting to hatch with my own eggs through the winter so I'm ready for the spring eggs.
Here are some more pictures of the progress(I just added this stuff tonight!)
Here's the incubator with the table top liner and light inside:
Here's the bator with the vents now added(I used the tops of those perfume bottles and made holes, then added some tape around them because they weren't tight enough.):
And here's an image of the vents up close:
Here's the inside view of the vents:
Here is the bator all lit up:
And here it is all lit up from the outside with cover on:
When I was a vet tech, our vaccines were delivered in styrofoam coolers just like those. I would contact local vets in your area, I am sure they would be happy to give them to you for free! (we had so many, we were throwing them out weekly!)