Since you're going to be running two of the Hertz HCX 165 I'd be tempted to go ahead and bridge. That will give you 300W x 2 channels at 4 ohms.
On that AMP you can run either high level or low level speaker inputs (if yours came with the optional low level input piggy back wires). If it were me, I'd try it both ways and see which sounds the best, choosing either the high level or low level speaker input method depending on which one produces the best sound. If you end up going high level speaker inputs you won't need the PAC line out converter.
With the Hertz I'd set the crossover switch to Full Pass and see what you can get out of it. If the speakers seem like they are bottoming out on the low end before you hit your desired volume, switch the crossover to High Pass and set the crossover frequency to somewhere between 80-120Hz.