First, let me just say WOW & Thank You for posting all the creative and incredibly nice work all has done on this units!!!
I know this isn't the normal but my wife & I are RV'ers and have started working on our basement coach fridge/freezer, turning it in a 'RV Keezer', LOL!
Since the Boss Lady won't let me have the whole thing, the plan is to build a 4" collar and use half allowing me only one 2.5Gal Corny Keg inside, with one Perlick 525SS faucet (on it's way) and a 5# CO2 (mounted on exterior) using a bulkhead adapter with ball-lock. The other 2.5 Keg will be filled and stored next to the keezer to naturally carb.
I sure don't have your carpentry skills or the proper tools but making it work
Still a long way from finished but here goes: