Here is how mine are setup, hope it gives you some ideas (note: they're for my Young Corns):
Overview of the tub:
A look inside (somewhat ornate):
Here is a picture of a Rack (incomplete in pic) I was building to fit the 15 Quarts, you can see how I put the probe inside:
The probe was kind of hanging in there, it isn't like that now as my current rack uses FlexxWatt Heat Tape and the probe is secured on that directly.
My corns haven't escaped this setup either, those black clips do a good job at keeping the space between the lid and tub secure.
Here is my current setup:
I was going to build it lidless, but the tubs would have a gap where the latches are, large enough for even an good side corn to escape... ...I'm purchasing a pro rack this summer though. My builds are crappy because I have no tools and I bought the wood pre-cut lol.
Hope this helped you get some ideas, good luck

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