If you're going to go with a two amplifier setup, run the Left/Right front outputs from the empeg into one of the amps, the Left/Right rear outputs from the empeg into the second amp. Use one of the amps to run your subwoofers, the other amp to the four remaining speakers. Tune/tweak your amps (crossover settings, output gain, etc.) to match the speakers they are driving.

My setup is a bit more complex.

tanstaafl.