Gator, unless you're smoking just a flat, you'll have to cut a packer cut in half to fit the #1. I just cut it in 2 pieces, lengthwise, then put the thinner "flat" portion on the top shelf, and the thick end (with the point) on the lower shelf. The thick end will cook slower, and help shield the thinner portion from the heat.
Here's an example of one I did awhile back in the #1:
http://smokinitforums.com/index.php?topic=979.0
Lots of ways to do brisket - this is just one that worked for me.