I too wanted to make a fermenter based on the same website you included in your post but I was concerned with cleaning so I did something a little different as someone prior to my post suggested. I cut a hole in the told, made a gasket out of some rubber that was for washing dishes in the kitchen sink, and bought an over-priced racking arm from Austin HBS. I'd make my own if I had it to do over again but that is just my $0.02 What I like about this design is easy cleaning and I just leave it in the fermentation cooler and hook my pump up to it to transfer to the kegs. The only thing not show in this picture is that I added a valve in the top so that I can add a little CO2 pressure and I also use two pieces of square metal tube each having 2 bolts with rubber feet and wing nuts that I use to add a little pressure to the lid. I'm uncertain if I remember what the civilized world uses for pressure but I had about 4 psi or about 0.3 kg-force/sq. cm. This one was simple to make but I'd strongly suggest not spending the $49 quid American and making your own racking arm. Whatever you decide let us know and take a few pictures.