Dual chassis - can speakers be biwired?

[Confused]

I think the OP simply wants to bi-wire a dual mono set-up. I think that without modifying the units internally this cannot be done, in a dual mono set up only two of the speakers binding posts are to be used. Rather disconcertingly, this is the two red positive terminals, the other two are not to be used. This can be clearly seen in the Configurator. You could of course simply use cables designed for this, with two plus ant the amp end, two cables and plugs at the speaker end.