3 kickers and 2 w3? I would not mix the two personally
W3's... which Kickers are they?
Best way?.. meaning most power from whatever amp you use?
If it was me I'd lose one set of subs and run either the Kickers or W3 alone. It depends on what Kickers you have and what will work in your car best.
The Cab will run either set all paralleled and put out some power but it will also need a bit of current.
I'd try to be more specific.
I loved my CAB's... they made pretty decent power and lasted longer than expected wired down on ok (not great) electrical.
Trying to install both amps and as many subs as possible might not be the answer here, I'd consider the vehicle and what will work well 1st. Enclosure/installation is everything... trying to haphazardly throw a bunch of gear in there usually won't end well.