A lot depends on how it was plumbed. All the connections into the multiport are threaded but depending on how the plumbing was set up around the multiport you may or may not be able to remove (and reuse) the plumbing. I did one and wasn't able to reuse the old plumbing because of this. When I redid it I put in unions so future multiport service could be done without cutting any plumbing.
In the pictures above, the unions into the filter are clearly screw on, but I can't quite tell with the others if they're glued or screwed on. Is this something that someone more familiar would be able to tell by looking at the pics?