Nice cage! (I have one too)
They don't need the middle grate in there, they'll have a lot more room if you leave it out.
You can put the stand on the right way, use the middle grate to create a shelf for the poop tray so it's underneath the cage but you still have storage space.
I have a Critter Nation Life Cheat photo album on my Facebook profile if you need it!
Cute babies, too!