hi!
a 680 is great for 2 girlies...
Hopefully you got the powdercoated? If not the galvanized metal starts to stink pretty fast when the pee soaks in. If you didn't you should be able to call/email Martin's. they are great people to work with!
When you get your cage, I suggest putting it together with zip ties. Not everyone does this but I found it much easier and easier to fix if I made a mistake.
the best best best rat information is all here on the forum. The information desk section of this forum is wonderful! THis is a link to the internet resources area. Very valuable information!
linkyHave fun with your kiddos and have fun decorating that cage!