I have two cages for which I got the interior retrofit from Kritter
Koncepts.  ([log in to unmask] or www.kritterkoncepts.net ) It
is made of vinyl coated 1/2x1/2 heavy woven wire, three levels with short
ramps and one is a trap door so it can be shut off if needed.  Got rid of
the old ramps and plastic shelves, which are really for cats.  The most
recent retrofit I got was a bit short front to back so had to send it
back so if you get one be sure to send Barry exact interior dimensions.
Profits support The Ferret Nook in Wisconsin.  I also have two more of
the same cages that had old broken bases so I appreciate the ideas others
have posted.
 
Carol O.,
Tucson
[Posted in FML issue 4688]