So you mean the Coroplast should come up the side 8-10 inches?
And what type of top do people usually use on C&C cages? He will be in a room where the dogs are not allowed. I don't really want it to be super heavy and I want to be able to open it fairly easily. It seems like in some of the pictures I looked through in the cage suggestions thread they didn't have tops. Was that just for picture taking purposes?
I did half of my top with the C&C cubes (this is where the heat emitter sits, as it is stable and permanent). The other half of my top is a wire closet shelve like LG said. It is attached with zip ties and opens and closes easily.
Here's some pics, Mine are the pink and blue themed cages (2nd and 3rd post on the page):