I have a tall (around 3'x3'x5') parrot cage that I am contemplating converting into a chinchilla cage. It is big enough to put two levels of shelving into it (making it 3 levels). The bars are very sturdy (for large parrots), but they are powder coated and scuffed from moving and storing. I suppose it is possible to paint it with something, not sure with what, though.
The floor is probably not good (same bar spacing) so I was thinking of covering it with 1/2"x1/2" galvanized steel mesh. I would wrap the mesh onto a wooden frame and elevate it slightly above the original floor to prevent it rubbing against the coated floor bars (using 1x2 firring strips)
For shelves I would use unfinished pine and screw them to the side of the cage with washers and steel screw-in studs and angle them down slightly to prevent accumulation of droppings on the shelves (maybe 3 degrees).
I was thinking of making a wide shelf with a wood box built on to it (bolted) for a hiding place and to have a solid floor to rest on.
I would also have a litter pan in one corner for getting the chinchilla in the habit of urinating in one area. (It will eventually go under the floor)
For cooling (if the air conditioning is not sufficient in the summer) I was thinking of using a small galvanized bucket (with lid) that can hold frozen water bottles that would be kept on the bottom of the cage. It will probably be wired to the side of the cage so it can't get knocked over.
If this is not a good idea I can build something from scratch.