Dan,
Looking nice. Can't wait to hear how it preforms. With the vent on the tail housing, you may want to consider running a vent hose underneath the tunnel and coming up to the engine compartment. I doubt that you would need a catch can, just place a breather filter in the end of the hose to keep foreign material from making it's way into the transmission. The gap between the top of the
oil in the shaft and the tali shaft vent is fairly small and increases the risk for
oil being expelled due to pressure. If
oil is expelled the air current under the car could distribute the oil on your rear brake rotors.
You could always wait and see if it is an issue; it may not be. However, it is a lot easier to place that hose now when everything is apart, then to try to take care of it later.
Jim