This might help. It looks just like this...
Step By Step
http://www.zpost.com/forums/showthread.php?t=455180
This picture shows the LOW speed Actuator. The High Speed one is on the other side. I would guess the Actuators probably open up a hole that is about 2 inches in diamater, allowing the left side and the right side (littery picture left to open up to connect to picture right) of the manifold to be connected on the inside. The low speed opens up the front of the manifold, and the high speed opens up the back of the manifold. You really need to get your hands on one to try to build one correctly. Sorry, mine is already mounted up...
(Oh yeah, and without a tune, Im not sure this idea would even work, as the ECU won't pump enough gas into your new setup, and you might get fuel starvation because you will be introducing a TON OF AIR) 
P.S. to swap the intake out is a pain in the ass. It takes 2 people, or one very determined person. It took me 10 hours to do this job by myself. Granted I could now do another one in probably 4 hours. There are just alot of little wires and plastic breather pipes your really need to document or take pictures of when you remove them, otherwise you might miss something. Some wires are near impossible to get to without groping around forever in the dark underneath the manifold.
Also please read this post about why you might not want to do this MOD without a TUNE.
http://www.e90post.com/forums/showthread.php?t=461277