If price isn't an issue I would look into cagesbydesign.com some really nice furniture quality display cages. I've even seen a few on craigslist in the past. If you know a good handyman you could always get them to build one similar to those on the website for less than half the price. Or you could cut out flaps in your stack and use all of the cages for one large enclosure if you are on a tight budget. Just be sure to sand the edges smooth when you're done.