it would appear that you have to connect the 2 AS controllers to the aquaero 1st then raise multiswitch over the top using treaded extensions. as i found this pic that shows the circuit board has no AS mounting holes.
Hey thanks for the pic. ;D Seems a little akward, but I suppose others probably said the same thing when I ram two Aquastream controllers on one Aquaero.

At least I will be able to get all the wiring to one place in my case so it will look a lot cleaner.