A friend {seriously!} is interested in a Scope rig with two A 16 Ultras for A/D - he has a lot of outboard and hardware synths - at least, until he starts using Scope

How many Z-Link ports will he require? The two you can get with a Pro bundle, or will he need the pro bundle plus a Z-Link daughterboard?
Sorry if this has come up, but I haven't found an answer in the archives or CW's site, yet.
Cheers.
Edit, I have an A16 Ultra that I use for A/D expansion of my RME Fireface, but have never used it with Z-Link. The manual's still boxed up from my last move =\