For coon in chimneys we do make an adapter that clamps onto the 9x11x30 or 36 double door traps. The adapter goes into the chimney while the trap remains above the chimney. This adapter is for smaller chimneys, but not necessary for larger chimneys. If the chimney is large, a 9×11 trap can simply be slid into the chimney with a rod wired through the trap to keep it from dropping.
Again, for larger chimneys, no special equipment is necessary as the 9x11x30 or 36 double door traps will work in a chimney as is. The adapter will work in smaller chimneys. In each case you still have a trap that will work for chucks, skunks etc. while saving money on an expensive singular-purpose chimney trap.