Just Google it. There is a wealth of info. Just one step beyond the Herbie by adding a Durso (open channel). Compensating flow now goes down the open channel instead of the emergency overflow, which now becomes a true emergency drain. I have it on my center drain DT with two MPs at each end. Took me three tweaks to dial it in. And it was my first attempt. Didn't touch it again for several weeks until I tied in a carbon reactor to my return manifold.
I got it converted to a bean animal style. All I did was add two 90s to the emergancy and adjusted it so when it fluctuates it doesn't go below the 90 or over it. Then added the emergency dry drain. Thanks for all the help guys!!