As promised multiple times, a set of pics to demonstrate how the jacket I made is removable. Reason being that wort and other stuff can get in the cladding and fester after a while. I made it removable so that it can be washed down and so that the keggle can be cleaned easier too.
And as a man who doesn't really like drilling more stainless steel holes than necessary, I chose to return from the HEX through the keg handle at the top.