I bought this to replace a much older version of the same model, which (thank goodness) is the same size and profile. The old one had a seal that failed and was leaking water from the bottom which in turn tripped the breaker.
Very easy to install. Unplugged the old one then removed the drain pipe and the tube from the dishwasher. I left the existing collar assembly in-place. NOTE: If you are going to install the new collar assembly, you will need to have some plumber's putty on-hand.
The most challenging part for me was releasing the existing unit from the collar as I initially turned it in the wrong direction (clockwise from left to right) and tightened it rather that releasing it - ultimately making it more difficult to release (DOH!)
One thing that is easily overlooked but is critically important: IF YOU HAVE A DISHWASHER CONNECTION, REMEMBER TO KNOCK OUT THE PLUG BEFORE CONNECTING THE TUBE TO FROM THE DISHWASHER! Alternatively, you can just keep a mop and bucket nearby.
In the end, the whole job took maybe 30 minutes (but could have taken less), and it works like a charm.