1)I used kitchen silicone on mine and it worked fine. I like having mine attached to the freezer so I don't' have to lift it up every time and I can still easily pour out of the faucets while I am working on stuff inside.
2) I used a pine 2x6 and wrapped it with walnut for appearances/insulation.
3) Once again, that is what I used.
4) I used the rustoleum all surface paint and it is tougher than I though it would be.
5) I did because it makes it look better and will likely hold up better. But be careful not to get star-san on the sealed wood, it will wash it out and you will have to sand/reseal it.
6) I think this would depend on your specific model of freezer.
Here is a picture of mine right after assembly to give you an idea of what I was talking about
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I like having the collar on the bottom because it is easier to be able to work on everything and knowing that is how it will stay when you close the lid. The downside is everything is 5.5" taller.
