I made a collar for mine. It makes it look pretty ghetto but it works. I could make it look a little neater but so far I haven't. What I did is take a 1" thick piece of wood that it at least a wide as your new tower. Drill a center hole for your beer lines and then drill holes in that so you can secure it to your kegarator. You then can get some wood screws and fasten your new tower to the wood. It takes some playing around with but it works.
You can make it look better if you want but I haven't really figured out a way and I keep my keg in the garage so it doesn't really matter.
I am interested to see if anyone else has a better idea so I can steal it.