I think maybe that bit near the still head is a sort of slobber box in case it pukes :think:
I don't want to sound negative but,here are the problems as I see them, Firstly you have to find a way to fit that still head to the keg, The thermometer will be of little to no use so it might as well go at the same time. Using temperature as a guide when running a pot still isn't successful in most peoples opinion. The diameter of the line going to the condenser seems a bit on the small side to me, it could be prone to blocking if the still puked enough of the wrong stuff, this in turn leads to pressure build up, not something you want in any still.
If you were to put it all onto a keg that condenser probably wont cope at the very least it would need to be in a bigger container of water, or you would be changing the water all the time to keep it cool.
For the work involved , and time spent changing everything around you could build a good 2inch or bigger pot still that would out preform what you already have.
If you do decide to build from scratch here is a good place to start.
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