I thought that I would add to the discussion with my project as well. I used a 10 cuft Magic Chef bought at Home Depot. It's big enough to fit a 1/2 barrel (Coors and Miller will fit) and a slim 1/4 next to it (or a regular 1/4 on top of the compressor). With some planning, you could probably get up to for 1/6th's but they aren't too available in Denver.
I went with a wood collar instead of a tower. My collar is 2 x 4's ripped down 1/2" so that I could reattach the hinges to the existing holes in the freezer. She works like magic!
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