I am 2ch. Old school amp/pre amp so I'll be using the speaker level inputs.

Most subs seem to have only one set of high level connectors - inputs but no outputs. You wire the mains in parallel to the sub and the sub presents such a high impedance load that the main speaker signal path is unaffected.

As you all know, Outlaw provides in and out high level binding posts so you can pass the signal through and impart the effect of the crossover on both the sub and the main speakers (in this case, some small stand-mounted monitors rolling off at about 70Hz)

My question is:

Do I have to wire my speakers off the sub, or can I used the same wiring approach used on other subs - wiring in parallel. I understand that the full freq content will be going to the main speakers, but that is the case now. All I need to do is dial in the xover for the sub and I should be in business?

I don't see any problem with wiring in parallel, but I haven't ever tried it myself. You could bounce the question past Outlaw support via phone or their online support page if you want.