I have actually been considering doing this myself. Using a Love controller would allow you to maintain perfect temps with the fridge. I'm thinking about making a simple 2x4 framed box, insulating it, and then sticking the fridge (door removed) in the side. Using a thermowell stopper on the carboy would allow to to maintain perfect temps in the cabinet.
"Brewers enjoy working to make beer as much as drinking beer instead of working."