The funny thing, Freezer, is that your nickname here reminds me of a set-up I saw once at a trout lake up in BC:

Find an old refrigerator (or upright freezer). Make a hole in the back and duct out from it to a sealed brick (or some kind of other) firehouse.

This method takes a lot of tending and stoking, but is an awesome way to cold smoke without direct heat. The fridge racks will handle whole fillets or even sides of big fish, and access is as easy as it gets.