I've built them before and used one for my jungle carpet, you can get away with high quality 3/4" plywood because it's only temporary. As for affixing it?....I don't. I simply cut it to the exact dimensions that it needs to be, so in order to install it and remove it you actually need to pry up on the cage top a little bit to get it into place. The cage itself holds it in and no baby snake, regardless of species will be able to push past it.