So I got a cage off craigslist that looked deceivingly like a FN cage. It turns out it is actually the feisty ferret cage. That's all fine and good because I can still order custom sized pans (that and the price was VERY good). My dilemma is dealing with the rust. I've been at it for a good hour and a half. I've been using baking soda mixed with some water. Vinegar and water, and a sponge. So the pictures are of what's left after all the scrubbing. I still have some more work to do, but is my chinchilla in any danger? The pan will cover the worst parts, but there are some on the bars that I don't think I'll be able to completely remove.